Category: Radio

What is Bluetooth Technology?

Bluetooth technology comes about due to an amalgamation of different wireless technologies. The specifications of this technology enable the unification of these technologies, thus forming Bluetooth technology. As a technology that relies on an open wireless protocol, Bluetooth enables data exchanges over short distances. However, radio waves of the shorter length are necessary; to facilitate the transfer of such data from fixed devices to mobile devices. In the process, the technology helps to create PANs (personal area networks). Ericsson was the first company to develop Bluetooth technology. Other firms such as IBM, Nokia, Intel, and Toshiba later joined Ericsson, to formalize the technology, thereby setting a wireless global standard. Bluetooth technology fundamentally functions as a cable-replacement technology. Accordingly, the technology allows users to connect different devices, such as computers and PCs, mobile phones, MP3 players, and headsets. Bluetooth technology aims to phase out cables as a connector to closely spaced devices. Devices with Bluetooth technology support direct communication amongst themselves, without having to use any cables. Such devices can communicate instantaneously with each other, so long as they are within the range of the Bluetooth technology.

How Bluetooth technology works

The core system of Bluetooth technology comprises a baseband, an RF transceiver, and a protocol stack. A Bluetooth device entails an adapter. Either such an adapter can be in-built, for example in a certain device, or it can take the form of a card that allows the user to connect to the device in question. The instructions for the use of a Bluetooth adapter, embedded into the device in use facilitate the channels of communication with various devices. A harmony of the radio ranges of two connected devices facilities the recognition of the link managers of the two devices. As a result, LMP (link management protocol) executes a peer-to-peer message exchange (Franklin, C, & Layton, n. d., par. 2). The LMP then establishes a packet size negotiation and setup. In addition, a reassembly and segmentation of the packets occur, when the need arises. The presence of a service delivery protocol is important, because it joins a piconet to a Bluetooth device. In this case, the role of a device is to inquire on the available services that the piconet provides. A global Bluetooth identification exchange often occurs between the two devices in use. Once their profiles match, the establishment of a connection setup is then realised.

The hopping of Bluetooth frequency occurs in timeslots, implying that the signals of this technology are free of any interference from secondary signals due to their ability to hop away to an entirely new frequency, following a reception or transmission of an individual packet. Bluetooth technology has the potential to support a data channel of the asynchronous type. Moreover, the technology can also support up to three synchronous voice channels, at the same time. In addition, Bluetooth technology offers parallel support to both synchronous voice and data in tandem. The underlying principle of operation of Bluetooth technology is that of master and slave. Accordingly, some devices have to wait a while, as other devices execute their operations.

Bluetooth History

Both the logo and the name Bluetooth are the trademark of a company called SIG (Bluetooth Interest Group). SIG is a privately owned company, established in September 1998. The company merges leaders in the computing, telecommunications, industrial automation, network as well as the automotive industries. It is the responsibility of Bluetooth SIG to support and encourage the development of research in the areas of Bluetooth technology. Various promoter member companies are part of Bluetooth, and these include Ericsson, Microsoft, Intel, IBM, Agere, Nokia, Motorola, and Toshiba. Sven Mattisson and Jaap Hartsen developed the Bluetooth specification in 1994. At the time, the two were employees of Ericson Mobile Platform, a communication firm located in Lund, Sweden. The frequency hopping spread spectrum acts as the foundation for Bluetooth specification (Bluetommorrow, n. d., par. 5).

The SIG later on formalized this same specification in 1998. Currently, more than 11,000 global organizations are members of the SIG. The name Bluetooth was for the first time coined by individuals credited its development. Initially, these developers used the name Bluetooth as a code name about the wirelesses technology but over time, it stuck. The word dates as far back as the 10^th century, and it refers to King Harald Bluetooth of Denmark. During his reign, the Danish King was quite influential in helping to bring together the Scandinavian countries at a time when this particular part of Europe faced clan feuds and wars that threatened to tear it apart. There are two reasons why Bluetooth SIG founders felt that the name they chose was appealing. First, the development of this technology took place in Scandinavia. Second, the technology connects various industries including computing, cell phone, and automotive markets, among others. Bluetooth is a wireless technology that combines and simplifies various types of wireless communication to form a single, low-cost, low power, globally available, and secure radio frequency.

Variability of Bluetooth technology

There are numerous areas where Bluetooth technology finds application. First, Bluetooth technology is used communication between and wireless control of a mobile phone on the one hand, and its hands-free set, on the other hand. This remains one of the most popular applications of Bluetooth technology. Second, Bluetooth technology finds use in the networking of personal computers, using wireless technology. In this case, such personal computers are usually located in confined spaces. Furthermore, such a wireless networking also demands less bandwidth. In addition, Bluetooth technology is also applicable in the output and input devices of personal computers, thereby facilitating wireless communication. Some of the devices in use here include the keyboard, mouse, and printer. Another application of Bluetooth technology is during the transfer of contact details, transfer files, reminders, and calendar appointments between various devices that have object exchange (OBEX). Bluetooth technology has also found use in conventional wired serial communications replacement in test equipment, bar code scanners, medical equipment as well as traffic control devices. Additional devices supported by Bluetooth technology include Global Positioning System receivers, digital cameras, and receivers.

Traditionally, infrared has found use in controls, but Bluetooth has now assumed this role. The technology is also ideal in applications that rely on low bandwidth, where the desire is to have a cable-free connection, as opposed to a higher bandwidth, such as USB. Bluetooth technology is also important when a user wishes to send for example, small advertisements from one device that is Bluetooth-enable, to a similar device. Bluetooth technology is a wireless bridge between two Industrial Ethernet networks (Bluetommorrow, n. d., par. 5). In the medical field, Bluetooth technology has found use as a transmitter for sensor data within short-range distances, from various medical devices to such other devices as the set-top box, mobile phone, or even a dedicated telehealth device).

Security

There are three security models through which Bluetooth technology can operate. Mode 1 is the non-security mode. Mode 2 guarantees security of the device only at the service level following the establishment of the channel. On the other hand, Mode 3 offers security at the point of linkage, before the establishment of the channel. An individual Bluetooth device consists of unique device address, with a memory size of 48-bit. Response to challenges characterizes the authentication scheme of Bluetooth technology devices. Therefore, symmetric keys accomplish encryption. The establishment of a channel of communication between two Bluetooth devices facilitates in the creation of an initialization key (Foley, 2009, par. 2). By inputting a Personal identification Number, followed by the creation of an initialization key, the devices attains authentication. Accordingly, the PIN or passkey becomes the prime concern for the security of a Bluetooth technology device. Like other keys, shorter keys appear more vulnerable to security hitches, compared with the longer ones. Once a hacker discovers the passkey or PIN of a Bluetooth technology device, he/she is in a position to compute the initiation key and accordingly, the link key. To avoid the vulnerability of a Bluetooth technology device from appearing quite vulnerable, one of the solutions is to ensure that the passkey is long.

Reference List

Bluetommorrow (n. d..). Bluetooth technology. 2009, Web.

Foley, M. (2009). The grass is always greener on the other side of the ocean. Web.

Franklin, C, & Layton, J. (n. d.). How Bluetooth Works. 2009, Web.

The Decade of Unity

Immersed in fairytale flamboyance and a flashy show of grandeur, the early twentieth century was positively engrossed within America’s newfound opulence. Similarly, the 1920s welcomed the optimism that came with the better part of the premature century, heralding a strong sense of togetherness throughout. Unity, the defining aspect of the 1920s, translates directly to ”a state of being united or joined as a whole” (New Oxford American Dictionary). In a time where organized crime, the telephone, sports, and the mass media were rapidly on the rise, unity was an ever-present factor of the decade, steeping the decade in a rich cadence of togetherness and camaraderie as a young America continued to discover her charm in light of the rather devastating stock market crash in the late 1920s. Further entwined as a whole as a result of the entertainment industry and the radio, the 1920s can be befitted as the “Decade of Unity” due to the prosperity experienced by many throughout its course.

Of the numerous cultural influences that served to further unite the country, it is perhaps live entertainment that truly solidified unity through the entertainment industry. Initially, it was an unspoken rule that, within the social hierarchy, only the wealthy were privy to forms of sophisticated showbusiness; however, as the decade continued to prosper with major economic and financial success in the stock market, it was with marked optimism that those born of lower social class were able to accumulate both the means and time to indulge in a luxury previously deemed unfit for them. Not only did the common bulk of society benefit from the rise in live entertainment, but Broadway, in particular, experienced a large influx of audiences during the 1920s (Edelman et. al 2). This is largely due to the fact that the mid-twenties heralded numerous stage productions that permanently resided on a stage for the term of their run, bringing in a large mass of audiences and revenue (Edelman et. al 2; Benson 3). In addition to the trend of live entertainment through Broadway, dance also aided in the unity that can be associated with this particular decade. The “Charleston” dance became immensely popular during the rise of Broadway, as it was not only affiliated with the large musical numbers on the stage but was eagerly embraced by the “rebellious youth” of the time (Benson 3). It was also thought that, for many, the flapper represented “equality and sexual freedom” for the post-war effort, garnering an occult following for its powerful message of nonconformity (“Jazz Age” 1). The active acceptance of live entertainment trends served to unify a great many, as gatherings were quite common in order to share and revel in the current rage of the decade. Many also accumulated in order to simply converse about the happenings of the day, with conversational topics revolving around the current productions and dance trends. Live entertainment certainly played a hand in the overall unity and optimism of the 1920s, concocting a period of togetherness experienced by those who dared to embrace its flamboyance.

In correlation with the live entertainment industry, the ‘Jazz Culture’ of the decade aided in solidifying the sentiment of overall unity between the American people throughout the 1920s. Jazz clubs spread like wildfire across popular cities, with the speakeasy culture only further igniting the thirst for live music and entertainment in a casual setting. As it can be seen, Jazz Culture appeared to be the spark that was needed in order to kickstart modernized consumer culture (“Jazz Age” 1). It was with conspicuous sanguineness that the general public received jazz clubs, as it was perhaps this aspect of the culture of the time that truly redefined ideas of nationwide unity (“1920s” 2). For a time, the barriers of the race were begotten with haste, bringing whites and blacks together in the search for the carefree demeanor so commonly associated with the decade. As it was, much of the Jazz Culture stemmed from African American influence, lending itself to the diminishing of segregation during this time; however, it is to be noted that, despite the lessening of racial barriers during the 1920s, racism was still a very prevalent and pressing societal issue until much later on (“Jazz Age” 1). Furthermore, the lure of jazz clubs eventually led to the rise of flappers, defying any cultural standards of the past through the unity of black and white women together. In a time in which feminism was a rising concept, the movement relished the limelight that was wrought on by the flapper trend, moreover lending itself to the concept of overall unity throughout the country (Benson 1). Overall, the introduction and subsequent popularity of Jazz Culture undoubtedly played a role in the trademark optimism and togetherness of the 1920s, ushering along a nation already steeped in a resolute desire to gather and grow as a whole.

Lastly, working in tandem with the aforementioned forms of live entertainment, the rise of cinema also greatly contributed to the successful unification of Americans across the country. Similar to Broadway or a jazz club, the commonplace gathering of a cinematic theatre allowed for many to gather in a singular place, resulting in an opportunity for new bonds to be forged between strangers. For example, with the establishment of Walt Disney Productions in 1923, adults and children alike congregated together in order to watch experimental animation films, drawing together a great many over a common topic (Edelman et al 5; “1920s” 5). In addition, the rise in “talkies”, or films with sound, led to an increase in cinematic discussion amongst the public, once more garnering enough attention to bring people together (Edelman et al 9). With the cinematic industry bringing in so many audiences, it became one of the most affluent industries of the time, far surpassing Broadway with the revenue that it generated (“1920s” 8; Benson 3). The rise of this industry instilled hope within a great many, as job opportunities began to grow in rapid succession. In light of so much positive change, the American people were brought together regardless of color, race, and age, giving way to a decade steeped in togetherness and comprehensive unity.

As more attention was garnered by these establishments, other upcoming technological breakthroughs were aided by the sudden burst of media attention—the radio, for example, was perhaps the subject of the most benefit.

In conjunction with the growing popularity of communal places of entertainment, the quick advancements in radio technology only served to better unification between the American people. Prior to 1921, although the majority of premature radios were undeniably functional, most were crystal sets, which were notoriously arduous to operate, tune, and function (“1920s” 8; “Radio Technology” 2). Thus, many people disregarded the radio as a household appliance, meaning that the subsequent boom in commercial radio use was all the more impactful upon the whole of American society (“1920s” 8; Howley 1). In order to improve upon the preexisting model, inventors and scientists working in conjunction to better vacuum tubes, an internal component of transmission technology that is often attributed to the overall success of the radio later on in the decade (“Radio Technology” 2). The initial improvement of the radio meant that it was no longer demanding of convoluted thought, resulting in the commercial popularity experienced in the years following 1921 (“1920s” 8). This particular invention brought a myriad of people together due to the first broadcast of the presidential election of 1922, as the importance of what was being announced once more drew many together over a common topic; subsequently, as radio technology continued to progress, people would soon begin to gather over daily news and music, further substantiating the unity of the American people.

With the amelioration of radio technology, the wealth of new knowledge led to the creation of the first radio station, bringing a plethora of Americans together as never before. Dr. Frank Conrad, who was an engineer hailing from Westinghouse Electrical and Manufacturing in Pennsylvania, is credited with beginning the first commercially successful radio station, the likes of which revolutionized the era of mass communication (“Radio Technology” 2). Despite the licensing Conrad had obtained in order to operate his station, the idea did not initially resonate with the public; as of the decade, wireless technology was still new, and many were hesitant to embrace it immediately after its birth. Additionally, the amalgamation of the post-war effort and the Great Depression rendered the use of the FM radio nearly unattainable until later on in the decade (“Radio Technology” 2-3; Howley 1). However, as many bands began to set their music to physical records, people began to buy into the idea, with radios becoming greatly successful in a consumer culture with the rise of more radio stations as the decade progressed (Radio Technology” 2; “1920s Science” 9-10). The first radio station brought many together, as the invention itself required that families gather around the singular unit. Additionally, the relative practicality and affordability of the unit and its services made it a large contender for the epitome of all-encompassing unification of the American people throughout the 1920s.

Lastly, as radio consumer culture skyrocketed, advances in the overall design of the radio led to a multitudinous of people coming together and contributing to the widely acknowledged tone of unity and optimism throughout the decade. Contrary to the primal radio of the early 1920s, the rather compact and efficient design established by the end of the century only served to further unify the American people (“1920s Science” 10; Howley 1). For example, the revolutionary invention of the car radio in 1927 not only allowed for superfluous excess in technological advances but allowed for the success of bands and the betterment of unification between individuals (1920s” 6; “1920s Science” 9-10). With music once more acting as a common bridge between two potential strangers, the radio served to draw a great many together, akin to the entertainment industry through its ability to spark common conversation amongst those unfamiliar with one another. As a result, the compact household radio was normalized, bringing Americans together in a new era of communication and entertainment.

Further entwined due to the entertainment industry and the radio, the 1920s can be deemed the “Decade of Unity” for the success experienced by many throughout its course. The radio and the entertainment industry—both defining aspects of the decade—were vastly important to the overall theme of the decade, as both served to unify the general public over a common topic. Due to the news and culture of the time, the 1920s became a prosperous decade steeped in togetherness and unity, marking it as a time of exponential growth and potential for those who dared to embrace its opulence.

Introduction

Simulation is a standard method in the toolkit of modern engineers; before a piece of equipment, a car or a telecom network is built, it is tested in a computer model that reflects both the object that is tested as well as its surroundings. This project aims to describe the main challenges for radio network simulators in the context of a “beyond 3G” scenario. After an elaboration on the current practices around simulation in the design of radio systems and networks, the project concentrates on the characteristics of the “beyond 3G” scenario, and the challenges it poses to radio network simulators.

Interconnecting building a,b, &c

Technology to Be Used: Wireless Networking

Interconnecting 3 Departments each having a LAN1, LAN2, and LAN3

Building LAN1

All computers will run on Windows 2000 server and will have a wireless NIC with Outlook Express as the mail client software.

They will be required to run software applications such as Microsoft Office Professional (includes suite of applications including, Word, Excel, PowerPoint, and Access) and Great Plains Accounting Software (for personnel information, payroll, inventory, accounts payable, accounts receivables, quarterly and annual reports, and tax documentation). The two applications will be supplied to all the staff in this department to enable them to access the documents and information written in those applications.

However, only the data that is required to be used by all members in this Department is to be shared within the network.

You need to configure all computers as Clients for Microsoft Networks, and enable File and print sharing, and share all the peripheral devices such as printers required in the network. All these workstations will communicate through a wireless router. DHCP address or Static address can be used.

How to Create a Wireless Network

Computer networking is a great way to collaborate with other computer users in your home or office. While it is becoming increasingly easy for the basic computer user, it can still be a difficult, frustrating experience for many people.

Steps

• Decide on what type of network you wish to install. We will be covering how to install a wireless network including 2 desktop computers, 1 laptop, and a High Speed Internet (HSI) connection. If you wish to install a wired network, this manual is not for you.
• Purchase the following items for your Wireless Network:
• Wireless router (with switch)
  • PC wireless adapters for the desktop computers
  • Laptop wireless adapter for the wireless laptop
• Connect the wireless router to your High Speed Connection by turning off all units, including the computers. Simply use an Ethernet cable (which usually comes with your High Speed Internet Connection) to connect your HSI modem to the WAN port on your wireless router.
• Open your desktop computers and install the PC adapters, or purchase USB adapters that do not require you to open your computer. Also install any necessary software on each machine. Older operating systems need some drivers installed.
• Install the wireless PC card on your laptop, and install the included software. Then, shut down all computers.
• Turn on your new items in this order:
  • Your HSI modem (wait for all lights to return to normal).
  • Your New Wireless Router (wait for it to start up fully).
  • The computers. They should find the wireless router and connect to the network and the internet through the new router.

Tips

• To create a network that does not include internet access (or to ensure that your computers are networked), be sure to enable Print and File Sharing on all computers. This is done differently on the Macintosh, Linux and the Windows platform.
• For Windows XP and Vista, go to Start > Control Panel > Network Connections (click “Switch to Classic View” if you cannot see the Network Connections icon) > right-click on your Local Area Connection Ethernet adapter > Properties > check File and Printer Sharing for Microsoft Networks > Click “OK”
• For Macintosh OS X, click on the Apple menu on the Menu Bar and click on “System Preferences…”. Then, click on “Sharing”. Then you may select which service that you want to be shared on your wireless network. For further support, click on the Apple Support Page link for sharing on your wireless network. Apple Sharing Support

Warnings

• Turning on your equipment in the wrong order could cause your new setup to not work! Be sure to power on each item in the order. It does matter.
• Remember to set up your security settings to prevent unauthorized access to your network. WPA encryption is much more secure than WEP.
• Also remember to change the default passwords and usernames on your wireless router. Many wardrivers will travel around finding hotspots and then trying the default codes for that type of access point. This could result in you getting locked out of your router and having to manually reset your network.

Sources and Citations

• Wireless Networks related help.
• Detailed Wireless Network Setup Tutorial.
• 5 Ways to improve your Wireless Network.

Jack H, James Quirk, Papa G, Tom Viren, Rick Davis, Alfons Van Hees, Imperatrix, Joe Hamilton, Ben Rubenstein, Richard, Sondra C, TSS888, Jonathan E., Travis Derouin

For Email services, you will use Outlook Express to configure email accounts for all these workstations. Other peripherals like printers that need to be shared should be shared from the computer they are locally installed. If all the above tasks are performed perfectly, the LAN in the first Department should work properly providing all the services it’s meant for.

Building LAN2

This department consists of Business and Finance. This Department handles the accounting of the whole Company since these acts as the Headquarter. The flow of money in and out of the company is controlled here. However, this department will work under the supervision of the Administration Department hence the need for networking.

All computers will run on Windows 2000 server and will have a wireless NIC with Out Look Express as the mail client software.

They will also run applications be required to run software applications such as Microsoft Office Professional (includes suite of applications including, Word, Excel, PowerPoint, and Access). Since it’s a finance department, accounting software, in this case Great Plains Accounting Software (for personnel information, payroll, inventory, accounts payable, accounts receivables, quarterly and annual reports, and tax documentation), will be supplied to all the staff in this department. The two applications will also be supplied to the other staff in the other two departments to enable them to access the documents and information written in those applications.

However, only the data that is required to be used by all members in this Department is to be shared within the network.

Creating a LAN, you need to configure all as Clients for Microsoft networks, Enable File and print sharing. As for me, I would prefer use of static IP addresses instead of Dynamic IP addresses. All these workstations will communicate through a wireless switch. Outlook express is then configured for email which will work through the internet.

Other peripherals like printers that need to be shared should be shared from the computer they are locally installed. If all the above tasks are performed perfectly, the LAN in the first Department should work properly providing all the services it’s meant for.

Building LAN3

The last Department is for the Consultants. As the Department of Business and Finance, this department also works under the supervision of the Administration. However, it must also work together with the Business and Finance Department calling for the three departments to be networked. This LAN will have an equal look and performance like in the department of Administration.

However, this office in Building A being the headquarter and center of operation, it’s in this department (department of Consultants) that all networks will be controlled. The mailing server, Microsoft Exchange Server, Internet connection server, and the PBX systems for phone services, all mounted in a server cabinet. For the security of the company’s data, information, a secure room with proper heat and air conditioners is reserved to store the server cabinet. Only the authorized persons like the Systems administrator are around access to this server room.

Interconnecting the three LANs and Internet Connectivity

All the workstations in each department connect through a wireless router. The three wireless routers can communicate using a single wireless or wired router. This router is meant to work as a gateway server. This router will however be connected to a T-1 line for internet services.

T-1 line system enhances data and voice communication For the emails the mailing server, Microsoft Exchange server will also be connected to a gateway router.

A T1 line operates much like any other high-speed connection, and will connect to your LAN via a router just as a cable modem would. The only difference is that most of the time and special router is needed to connect via cable, and then you can take that into another router that will feed all of your machines in the network. With a T1, you don’t need a special router. You should be able to wire it right into your main router and have connectivity.

Depending on the kind of router that you currently have, if you have problems, it might only be because you need to use a crossover instead of a regular CAT 5 Ethernet cable, or you might need to plug it into a main port, uplink port, or LAN port (some routers, like the Linksys Wireless 802.11G, support all of these). (Marc Melvin 9/23/2004).

T1 carrier is one of the most popular leased line options for digital transmission that offers high speed internet connectivity at 1.544Mbits per second. A T1 line is comprised of 24 individual channels, each capable of transferring data at 64Kbits per second. With T1 Internet connection, you can have uninterrupted and reliable data transfer within seconds. In normal phone lines, voices are transmitted through copper wires as analog signals and you can transmit data at around 30 kilobits per second with your normal modem. A T1 Internet connection, on the other hand, is capable of carrying 24 digitized voice channels at the speed of 1.544 megabits per second.

A T1 carrier can carry 192,000 bytes of data per second – nearly sixty times more data than that of a normal residential modem. T1 Internet connection is capable of providing uninterrupted data transmission which you would not get if you use ordinary modems. If you want to transmit audio or visual data through your residential modem or through your phone service you have high risk of getting jammed since the speed is so slow. With a T1 service, you can eliminate this risk significantly.

Internet service by service providers converts all voice calls as analog rather than in digital format, which not only takes longer time but frustrates customers now that high speed is available. With a T1 line, you not only increase the speed of your data transmission but also save time for your valuable online work.

This article may be reproduced wholly or in part without written permission provided the byline, resource area, and any hyperlinks remain in order to give proper credit to the author.

Creating LAN in building B

When building a network, the type of technology matters though in most cases, it is possible to integrate all the available technologies. This building is very close to building A and therefore, it is possible to use cables to interconnect building A to building B.

To configure a wireless LAN in this building, we must put into consideration, the type of wireless connectivity we shall use due to distances and locations of offices within this building. By this I mean, the manager could be facing right side of the Receptionist, custodians on the right side of the Manager while the IT Support person and the consultants on the left side of the custodians. All these workers need to communicate and a proper network is required to facilitate this.

This LAN will be used to access internet from the gateway router in Building A, sending and receiving mails and uploading data from Access Databases using FTP. Software applications such as Microsoft Office Professional and Great Plains Accounting Software for accounting purposes.

All the workstations having each a wireless NIC and running on Microsoft Windows 2000 server operating system will communicate to a single wireless router. Workgroup names and the IP addresses will then be supplied to each one of them. Outlook express should also be configured as a POP3 client which should work through the internet to Building A’s Exchange email server.

Linking building b to building a

The purpose of linking the two LANs together is for email services, internet services and phones services. Email and internet services will be configured to work in the same way- emails will be accessible through the internet.

When connecting building B to building A, the best method I would prefer is a point-to-point connection. Being that there will also be a connection between building A and C, a point to multipoint connection is preferable such that an Omni will be mounted on building A which must be at the line of site with the two buildings. Then on buildings B and C, a Radial will be mounted to communicate to the Omni in building A.

Wireless Connection

Point-to-Point Microwave

Point-to-point microwave radio links have long been the technology of choice for cellular base station backhaul. With point-to-point, microwave radio and antenna is placed at the base station facing a similar radio and antenna at the Base Station Controller. These links carry one or more E1/T1 trunks, or their fractions. Point-to-point radios are available in a wide variety of radio frequencies, many of them dedicated worldwide to point-to-point applications. A large number of vendors supply a wide variety of microwave radio products at affordable, but somewhat high, prices.

Base Station Feeding Using Point-to-Multipoint

Point-to-multipoint technology is a highly attractive alternative for implementing mobile base station feeding solutions. Point-to-multipoint presents significant advantages over traditional backhaul methods such as leased lines and point-to-point wireless. In a point-to-multipoint architecture, a central site connects to multiple remote locations, sharing frequency spectrum and equipment. When used in a base station feeding application, several cellular Base Transceiver Stations are connected to a single radio and antenna at the Base Station Controller.

This concept allows for smooth network growth and expansion, and facilitates optimization as user patterns change – by allowing dynamic allocation of backhaul channels to any base station. When a base station requires more channels, additional bandwidth is simply allocated on the backhaul link by a network management command, limited only by the total capacity of the central site.

With point-to-multipoint there is no need to license individual links. Point-to-multipoint systems are licensed on a one-time basis. All additions and changes are covered by the original approval, and do not require regulator intervention.

Using a point-to-multipoint system requires a specific license from the regulator. The allocated frequency band is licensed for the exclusive use of the licensee. With the current telecom downturn, obtaining a point-to-multipoint license has become easier than ever. Once the operator owns this spectrum, the licensing issue is over. In cases where spectrum is not available to the mobile operator, it may be leased from the license holders, or backhaul services may be purchased from a broadband wireless access operator.

With point-to-multipoint, radio planning is performed only once for an entire area, using methods and tools similar to those used for cellular telephony. Adding base stations does not require additional radio planning, so long as backhaul capacity has been reserved for growth.

Installing base station backhaul in point-to-multipoint system is much simpler than in a point-to-point system. Once the point-to-multipoint central site is installed and radio planning is completed, connecting a new link becomes relatively an easy task. As the central site of the point-to-multipoint system covers a wide area, radio alignment at the mobile base station is easy and can be performed quickly, often by a single technician. With point-to-multipoint, the number of antennas at the Base Station Controller is greatly reduced.

Unlike the point-to-point solution, a single central site antenna serves multiple BTS sites. Typically, a maximum of four antennas will cover an entire area. This improvement not only decreases space requirements and wind-load on antenna masts, but also reduces the environmental and esthetic impact of backhaul deployment.

Point-to-multipoint systems offer significant cost savings over point-to-point. Since with point-to-multi-point, the central site radios and antennas are shared by multiple base station sites, the total cost of the system is reduced. In addition, due to mass production for Broadband Wireless Access applications, the cost of individual point-to-multipoint radios is lower than those of their point-to-point equivalents. All-in-all, point-to-multipoint systems can offer equipment cost savings of 50% or more, when compared to point-to-point systems. Moreover, point-to-multipoint systems also feature lower operating costs: There are fewer units to manage, and the remote terminals are managed as one system with the central site.

Unlike leased lines, a point-to-multipoint solution does not involve payment of an expensive monthly charge. It gives the mobile operator independence from its competitor, the fixed telephony service provider, and allows the cellular system to be deployed at its own pace – with no dependence on slow-moving, bureaucratic phone companies. Point-to-multipoint systems are orders of magnitude less expensive than installing private lines, which require digging and laying of copper or fiber infrastructure.

Cellular operators deploying point-to-multipoint systems for base station backhaul can, relatively easily, utilize the same infrastructure to provide Broadband Wireless Access services to business and residential users. Cellular Operators can thus capitalize on additional revenue sources by providing new services and applications using the same infrastructure and with minimal additional cost.

Alvarion WALKair Mobile Base Station Feeding Solutions

The WALKair Broadband Wireless Access System is a state-of-the-art point-to-multipoint radio system for broadband applications, which can provide an optimal solution for the mobile backhauling requirements. WALKair offers significant operational cost savings over leased lines and is much less expensive than point-to-point alternatives. Its modular architecture requires a small initial investment and features simple, fast and non-service-interrupting upgrades upon capacity growth or site addition. The WALKair system allows very high voice and data backhaul capacity, enabled by the high spectral efficiency of the radio interface. Spare capacity can also be used for Broadband Wireless Access applications, providing services to business customers.

RADWIN’s breakthrough WinLink™ 1000 Multi Point-to-Point architecture allows service providers and ISPs to provide multiple end-users with carrier-class services (TDM and/or Ethernet) and dedicated bandwidth from one hub location.

The Multi Point-to-Point concept builds on RADWIN’s unique Hub Site Synchronization (HSS) technology which synchronizes the transmission of collocated WinLink™ 1000 radios – thus eliminating mutual interference commonly experienced with collocated TDD radios. This allows for up to 16 WinLink™ 1000 units to be installed in the same site.

The Multi Point-to-Point architecture is ideal for a variety of target markets. Today, service providers and ISPs are using RADWIN’s Multi Point-to-Point architecture to provide their end-users with guaranteed dedicated bandwidth. Private networks such as enterprises are using the unique Multi Point-to-Point deployment concept to create high-capacity networks where each site enjoys its own dedicated connection.

The Multi Point-to-Point architecture allows service providers to benefit from a ‘pay as you grow’ concept, with fixed cost per connection and low risk in project development and cost. There is no need for a high initial investment in expensive hub sites such as the case with Point-to-Multipoint systems.

WinLink™ 1000 Multi Point-to-Point Benefits

• Deliver dedicated bandwidth per end-user
• Provide combination of TDM + Ethernet services
• Low entry costs; Scalability in network growth
• Easy planning – no need for radio planning
• No degradation in network performance as more users join the network
• Optimized for non-uniformly distributed high-end users

The Omni is connected to the gateway router in building A while the Radial will be connected to the router in building B.

Having connected building A and building B, all the employees in the two buildings should be able to have access to internet services, emails services and FTP services, all discussed below.

FTP services

The preferred server is configured to accept incoming FTP requests. The files that you want to make available should now be copied into the folder for access.

The File Transfer Protocol (FTP) contains a set of rules for transferring any type of file over the Internet between FTP servers and FTP clients.

Figure 1 illustrates how FTP works between the server and client. Both computers must be running TCP/IP over a network. The user makes FTP requests through a user interface (UI) which could be any FTP client software. The UI talks to the User Protocol Interpreter (UPI) that ‘talks’ to the Server Protocol Interpreter (SPI) through a default channel or port 21. PI initiates control and passes FTP commands through the connection.

As you can see by the diagram, the PIs not only talk to each other but also with the data transfer process (DTP) of each respective side. The DTP, in turn, is like a data pump. It receives a transfer request from PI and either sends or receives the data and passes it to the file system or storage device (hard drive). Port 20 is usually used to transfer data.

An FTP server is the most common type of information server and the most widely used method of Internet data storage and transport. FTP servers that hold large amounts of documents and files are considered archives. While most people access the Internet via Web browser, any file the user tries to download from the Web more than likely involves accessing an FTP server to get the desired file. A file sent from an FTP client to an FTP server is “uploaded” while a client “downloads” a file from an FTP server. To make an FTP server, you need a computer with FTP server software, TCP/IP connectivity and an Internet connection.

An FTP server can be accessed one of two ways: authenticated or anonymous users.

User FTP requires people to have an account on the server. They must enter a user ID and password to access the files. While logged in, all the files and information in the FTP directory structure are available to users, but they do not have the ability to execute arbitrary commands. This means that even though the user can access the files, they do not control the server remotely. A potential security problem with using FTP is that the password is sent as clear text. This means that people with programs called “sniffers” can detect and capture the user’s ID and password.

Anonymous FTP allows anyone on the Internet to access the server and download files. This type of server is desired when the host is not worried about security or wants users to have free access to the files available. Usually, a user ID or password is not required, but if it is the site provides the information for users.

You will notice that some FTP sites are faster or slower than others and that at times the transfer will have variable transfer rates. There are several reasons for these variations, mainly external to the server. For the most part, transfer rates are affected by:

1. The amount of bandwidth available between the server and the client site. A transfer can only be as fast as the available bandwidth.
2. The number of users logged on to the server and transferring files. The more users logged on and accessing files, the less bandwidth available for your transfer.
3. The amount of traffic on the Internet at the time of transfer. Even if you are the only one accessing a site, if the Internet is busy or slow, your transfer will also be slowed down.
4. How the data is routed across the Internet. Since packets are routed individually, they may not be sent across the same route. Remember, packets are routed through the fastest way the router can find at the time it receives the packet. This means that one packet could be routed to you in two hops while the next one may be routed three hops.

While FTP started out on a UNIX platform, it has been adapted to run on other operating systems. Today, most FTP servers are run on UNIX, Novell or Microsoft NT servers. While these operating systems include their own FTP servers, various independent FTP server packages are also available.

Reynolds, Joyce, and Jon Postel, “Assigned Numbers”, RFC 943, ISI, April 1985.

Internet Connection

Having created a LAN in this building (building B), and connected building B to building A, it is now possible to configure an internet connection. A point to multipoint connection is used.

This can be achieved by configuring the IP address to the router in building B and registering that address to the gateway router in building A. All the workstations connecting to this router should be able to have internet service.

Creating LANs in building C

This building is the third premises for this company. The number of workers in this building is similar to the number of workers in building B. However, two independent LANs exist, all running on Novel Netware.

The LAN architecture used is similar to the one in building Band A though Novel Netware is used. Here one machine is configured with Novell Netware Server while the workstations will run on Novell Client Software. The two servers will then connect to a router which will be used when linking buildings A and C.

Novell NetWare

NetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a PC, and the network protocols were based on the archetypal Xerox XNS stack.

NetWare Connect Services (NCS) Overview

NetWare Connect Services (NCS) is the networking technology infrastructure Novell is providing to telecommunications carriers. NCS offers full support for Novell NetWare applications. The NCS environment is a shared, multiprotocol networking platform that routes both IPX and IP traffic among attached networks. Customers connect to an NCS-enabled network via dedicated or dial-up connections. NCS offers a variety of opportunities to developers, including the ability to leverage Novell Directory Services’ security features, as well as the capability of using single sign-on for applications.

Introduction

NetWare Connect Services (NCS ) is part of the technology infrastructure that Novell is developing for data communication carriers to create a secure business-to-business information network, which extends current networks beyond their existing boundaries. The security, ease-of-use and connectivity of NCS, in conjunction with the quality, performance and reliability of carrier networks, create an open, highly functional data communications environment for businesses. NCS is an IP and IPX internetwork designed to complement other information networks.

NCS thus expands the information superhighway concept for inter-and intra-company communication and operation. It will allow businesses to reduce the expense of building and operating their own private internetworks.

A Public Network for Global Business

As the world moves ever faster toward a global economy, people and businesses need the tools and infrastructure that can ensure global transactions take place securely and reliably. There is no public network available today that has both the security and reliability of a NetWare network and the reach of the telephone infrastructure.

The net effect of NCS and the partnership between Novell and others will be the creation of a global LAN a worldwide network that provides all of the benefits of the NetWare 4.1 local area network, including high performance and ease of use. Businesses everywhere will obtain another notable benefit: they won’t be burdened with building, maintaining and administering complex wide-area networks, servers or applications. And they won’t have to replace existing operating systems.

Market Availability

NCS provides a platform for global internetworking consisting of multiple NCS-enabled networks with services provided by affiliated telecommunications carriers.

Novell’s first alliance was with AT&T. We have been working very closely together to define the standards of this first public version of NCS, AT&T NetWare Connect Service that is now available from AT&T.

Novell has also announced partnerships with Deutsche Telekom (Germany), NTT (Japan), Telstra (Australia), and Unisource (northern Europe) who each intend to offer their own NCS network service to business customers. These communications companies will work together to interconnect their networks, under the umbrella of NCS, allowing customers to easily access users and information located on any of the affiliate networks and provide developers an open and robust development platform with full interoperability.

In addition, Novell, AT&T, telecommunications carriers and other technology companies have joined in forming the Multimedia Services Affiliates Forum (MSAF) to further define this technology.

Developing Applications for NCS

Below are just a few of the many benefits you will receive when developing an application to run on NCS.

• Infrastructure to deliver genuine inter-and intra- enterprise applications.
• Familiar with open platforms for new and advanced applications and services.
• Leveraging Novell’s directory and security technology so that the developer can concentrate on unique application requirements rather than spending time reinventing technologies that Novell has already developed.
• Existing NetWare-based applications can be extended to NCS with minimal effort.
• Access to the global directory using standard Novell APIs.

Opportunities for Developers

Novell places tremendous value on the business relationships it maintains with its partners. You bring expanding market acceptance and brand momentum to Novell and its products. You also benefit by being aligned with the leading network operating system vendor in the industry. With NCS, you are provided even a greater opportunity. An opportunity to be aligned with the leading telecommunications carriers around the world, to broaden your applications’ reach, and to enter new markets you may never have been able to.

With Novell Directory Services, the Directory of choice by these worldwide carriers, a wide array of offerings are available to you for adding value to your applications. You can leverage the unprecedented security mechanisms within Novell Directory Services for user authentication, eliminating the need for you to develop your own security mechanisms. This also provides the ability for single sign-on to your applications-end users will no longer have the annoying task of re-entering username and password to use your application; it is handled transparently through NDS security.

The NCS global Novell Directory Services tree, has base objects and existing user information that your application can take advantage of, saving you time in building another address book.

There are unlimited applications and services that can be developed or enhanced to run on NCS. If it runs on an enterprise network, it should run unmodified on NCS. The rich development platform available with NCS provides you the ability to easily add value to your application, saving you development time and money.

The NCS Architecture

NCS is the networking technology infrastructure Novell is providing to telecommunications carriers. It is being developed with proven Novell technology. NCS provides full support for Novell NetWare applications. The primary features of NCS-enabled networks are security, reliability, ease of use, predictable performance, and cost effectiveness.

The strength of the service comes from its combination of the Novell local area network technology and the telecommunications carriers’ expertise in providing high availability wide area networking. The synergistic effect: a rich networking environment for application developers as well as end-users.

The NCS environment is a shared, multiprotocol networking platform that routes both IPX and IP traffic among attached networks. Customers connect to an NCS-enabled network via dedicated or dial-up connections. For seamless NetWare internetworking, NCS-enabled networks support mechanisms that provide users with information on NetWare services and resources available to them throughout the entire network. These resources include customers’ own corporate resources as well as other value-added applications and services that are available to customers based on a carrier’s implementation of their service.

Novell Technologies

NCS provides a fertile applications development environment, all with the tools you are used to. NCS is based on the following Novell products:

• NetWare 4 (supporting NetWare 2.x and 3.x)
• NetWare Directory and Security Services
• NetWare Link Services Protocol (NLSP) and IPXWAN
• NetWare Connect
• NetWare Multiprotocol Router
• NetWare Mobile
• LAN Workplace
• ManageWise

Infrastructure Protocols and Routing

NCS supports IPX and IP protocols. The carrier backbone uses NetWare Link Services Protocol (NLSP) routing. Routing Information Protocol (RIP), Novell Directory Services (NDS), static routes and services, and IPX default routes are supported for IPX customers. For IP customers, RIP, static routes, and IP default routes are supported. NCS accepts RIP or NLSP from customer networks; however, SAP is not allowed inside the carrier networks. Bindery Gatekeepers in the carrier networks are available to provide connectivity to NetWare 2.x and 3.x resources.

All network numbers advertised to an NCS-enabled network must be registered and all networks advertised as reachable to an NCS network are reachable by any directly connected customer. However, only routes to core services and the default route are advertised to customers.

Network Access

Users can access NCS through dedicated or dial-up connections. Dedicated access is currently available through Frame Relay. Dial-up access is available through an asynchronous connection or ISDN.

Client Software

A client can access NCS with three different options. An end-user could use:

• NCS client software that is offered by the carrier
• The standard NetWare client for LAN users or
• Third-party client software/third-party TCP/IP stacks.

Below are the components of the NCS client software provided by the carriers.

Component

Function

Standard NetWare Client

VLMsproviding basic NetWare connectivity

Dialer

Dialingand connecting to remote services (including NCS)

IPX and IP Protocol Stacks

IPXfor connectivity with NetWare LANs and TCP/IP for Internet access

WinSock 1.1

Standardinterface to TCP/IP stacks

NetWareEnd-User Utilities

Login,drive mappings, printing, and other network functions

InternetUtilities

NetScapeNavigator 1.22, Rapid Filer (FTP) and Host Presenter (Telnet)

BinderyGatekeeper Navigator

Access to NetWare 2.x and 3.x services

This component list was accurate at time of printing, but the components provided by specific carriers may vary, and this list may be updated periodically.

Network Directory

Carriers implementing NCS are using Novell’s Novell Directory Services as the network Directory. Novell Directory Services is providing the key security mechanisms for the authentication and certification of users accessing the carrier networks. The Directory is organized geographically based on the structure developed by the North American Directory Forum (NADF). Using this structure, companies are placed at a level in the Directory tree that is appropriate to their business reach.

For example, companies who do business nationally can appear directly under the country name, while smaller companies who do business regionally can appear under a state, province or locality name. Customers of NCS networks have the option of taking part or all of their directory available to their customers, suppliers and/or partners.

Added Value Services

There will be value-added services that will be made available to customers of an NCS network that depend upon the offering of the carrier. Such type of services includes access to information networks such as CompuServe and access to other services/applications that may be hosted by a carrier or by another company connected to NCS.

Providing a Service over NCS

If you have an application that you would like to make generally available over an NCS network to the network subscribers, that opportunity is available to you. In most cases, all that is required is that you subscribe to a carrier’s service and establish a connection to the network.

There are three ways that you can deliver a service over NCS:

1. Any application that runs on NetWare can be used with NCS. For example, if you have remote users that dial in from remote sites to access your network, you can use an NCS network as the conduit for that communication rather than a toll phone line.
2. You can set up a dedicated connection to your LAN to NCS and provide the service through the network. For example, if you have or are planning an online service, you can simply connect to NCS and immediately have wide-area connectivity for remote clients.
3. You can offer a service on NCS, but have the system actually hosted by the telecommunications carrier or some other third party.

Below is a diagram that depicts the components that comprise an NCS network as discussed above.

Process for Establishing a Connection to NCS

Below are examples of how a subscriber to an NCS network would connect to the carrier service and access resources.

Dial-Up Connection. John is a telecommuter working from home 3-4 days a week and he accesses his company network via NCS. His company, World Electronics has a dedicated frame relay connection to NCS. To connect through NCS,

1. John, loads his NCS client software.
2. He then clicks on the dialer function to connect to his company LAN; the dialer can be preconfigured with phone numbers depending on where John is dialing in from, or John can enter the phone number to dial on the fly.
3. Once this takes place, John is connected to a NetWare Connect dial-in server in the carrier network. This is where the first level of authentication takes place. Through NetWare Connect, John is authenticated via PPP.
4. If this is successful, John can then log in to the NCS global tree and/or directly to World Electronics corporate tree. During PPP authentication, John’s home server information within World Electronics is passed to the client via NetWare Connect.
5. Once this second level of authentication takes place and is successful, John is connected to his company LAN and has access to all his usual resources.

Based on John’s access control rights he may have access to other resources available on the NCS network that are outside his corporate network. John can also browse the Internet over the NCS network using any Internet browser.

Dedicated Connection. ABC Distributors has a dedicated connection to an NCS network so that their customers and remote sales force can always access their Sales and Inventory system to order products.

• ABC Distributors’ customers may access to ABCDistributors’ Sales and Inventory system at any time through the dedicated connections from their own LANs to NCS.
• Dial-in clients may access ABC from any dial-in connection to NCS.

Linking Building C to Building A

The connection between building A and building B is similar to that which should be used when connecting building C to building A. The two servers for the two LANs in building C connects to a single router which will be used to connect to the wireless systems for the purpose of the wireless connection between the two buildings (building A and C).A point to multipoint technology discussed earlier should be used. Internet connectivity, email services and FTP services will also be meant to work similarly. This new branch has been using dial-up internet access and email services through AOL. However, the configuration for internet and email services will be done as it was done in building C.

Phone Services for the Three Buildings

PBX System

Phone services will be essential for communication between the company and their clients and also among the company workers.

Initially, building C has been using a normal telephone service from the Local Telephone Company. But a PBX system will now be installed in each of the buildings ensuring effectiveness of Voice Mail, Call Waiting and Call Forwarding.

Standard PBX

PBX Definition: Premise-based definition of PBX

The term PBX stands for Private Branch eXchange. A PBX, sometimes known as a phone switch or phone switching device, is a device that connects office telephones in a business with the public telephone network. The initial central functions of a PBX were to route incoming calls to the appropriate extension in an office, and to share phone lines between extensions. Over time, many functions have been added, such as automated greetings for callers using recorded messages, dialing menus, connections to voicemail, automatic call distribution (ACD), teleconferencing, and more.

Today, PBX systems are expected to handle a wide variety of duties beyond simple connection to the public phone system. The range of features offered by a PBX varies, usually in proportion with the price of the equipment. Some of the main functions:

• Present a single business number that gives access to all company employees and departments
• Answer calls with a custom business greeting
• Offer a menu of options for directing the call, such as connecting to a specific extension or to a department
• Provide a directory of employee extensions accessible by inputting digits corresponding to employee first or last names
• Evenly distribute calls to a department among available employees through Automatic Call Distribution (ACD)
• Place callers on hold when they are waiting for an available department employee
• Play music or custom messages whenever callers are waiting on hold
• Take voice messages for any employee extension, for a department, or for the company in general
• Allow transfer of calls between extensions
• Conference multiple incoming calls with employee extensions
• Provide detailed call records and real-time system management

Of course, not every one of these features is available in every PBX system. The hardest feature to provide has been Automatic Call Distribution (ACD), and usually vendors charge a premium for products that include this feature. Other features that often get left out include integrated voice messaging, conference bridging for conferencing multiple outside calls, and detailed real-time system monitoring. Many times some of these features are not part of the base PBX system but can be purchased through add-on system modules.

Diagram & Operation

In a typical office environment, the PBX system connects multiple incoming phone lines to multiple telephone extensions. Basic PBX switches do little more than cross-connect these lines. As system price rises, functions are added. Some added features can be provided through software and/or firmware upgrades inside the basic hardware. For other features add-on modules are required.

Usually, the PBX device is a piece of hardware that hangs on a wall or mounts in a rack. Some type of patch panel is included that allows connection to internal and external telephone wires. Sometimes, PBX functionality is provided through software. In this type of system, a personal computer controls system operation and adapter cards and add-on modules provide connectivity.

Operation is fairly straightforward. Callers that want to reach someone in the company place their calls from any type of telephone. The call is routed through the Public Switched Telephone Network (PSTN) to company-specific lines leased on a monthly basis from a telephone company. The PBX system answers the call with a recorded greeting, plays a menu of connection options to the caller, and then routes the call to the appropriate employee extension or to a holding queue (ACD queue or hunt group) for a department, such as sales or support. In installations where the company wants calls answered by a person instead of a machine, the calls are first routed to an operator or receptionist who then forwards the call to the proper extension or department.

Calls transferred to an extension will ring at a particular phone, usually a desk phone somewhere in the office. If the extension owner picks up the phone the call is connected. If not, the call is usually transferred to voice mail.

When callers know what department they want but don’t have the name or extension number for a particular individual, they usually have the option to be sent to a holding queue to wait for the next available agent (employee) to take the call.

Many low-end systems do not offer any type of holding queue, and callers must know who they want to speak with before they call. Other low-end systems send callers to a “hunt group” – a list of phone numbers to try and find someone available. Hunt groups usually have the drawback that every extension number must be tried, in the same order each time, in an attempt to find an employee that can take the call. In such cases, the first extension on the hunt list usually gets swamped with calls while other extensions are used only when there is a heavy load. Another disadvantage of hunt groups is the time it takes to try each extension to find one that isn’t busy and has someone ready to pick up the phone.

Higher-end PBX systems employ a variety of techniques to assure that calls to a holding queue are answered more efficiently. The most prevalent approach is through the use of Automatic Call Distribution (ACD) queues.

A system with ACD queuing keeps track of which employees are already taking calls and how long it has been since each person finished prior calls. Incoming calls are put into the queue waiting for the next available employee and then routed automatically to the employee that has been off the phone the longest. ACD queuing evenly distributes calls to employees while ensuring a minimum wait time for each caller on hold. The ACD queue feature can add considerably to the cost of the PBX system but is often a major factor in customer/caller satisfaction. Serious businesses usually need the advantages of true ACD queuing.

VoIP PBX Solutions

Business communications have always been a challenging arena for management; subject to cost, function, reliability, and other pressures and concerns. The emergence of VoIP technology, and specific application to PBX systems via IP-based protocols, has provided an enormous opportunity for companies to reap many benefits.

Many companies today have multiple office locations around the country or around the world. Currently, each office uses its own PBX system and inter-office phone calls are routed through the PSTN and charged long-distance and international rates by carriers. Most companies also employ workers on a part-time basis who work from their homes. Those workers get reimbursed for telecommunication expenses they incur while performing their duties. It just makes business sense for companies to explore alternatives to consolidate their telecommunication systems and reduce costs.

The answer: A Voice-over-IP enabled PBX system in a virtual office model

Voice-over-IP (VoIP) is a fairly new technology for transporting voice calls over the Internet which allows users to realize substantial cost savings on long-distance and international calls. Besides cost-effectiveness, VoIP enabled PBX systems (or IP PBX) offer easy integration with existing telecommunications systems and are characterized with low operating costs as their upgrade is done through software updates rather than more expensive hardware replacement. Additionally, the technology simplifies the communication infrastructure (no need for separate voice and data cables) while offering high scalability.

Virtual Office models are used by companies that want to consolidate their communications, reduce costs and achieve more cohesive corporate images. To implement the model, a company has to install a single IP PBX system in its headquarters and distribute to employees IP phones or regular phones with VoIP adapters. Employees can make intra-office and inter-office phone calls by dialing PBX extensions. Such calls are routed through the Internet and are practically free. Company customers, on the other side, can dial a single inbound number plus extensions in order to reach the company’s employees. The latter receive the calls on their IP/Regular Phones at any location in the world with Internet connectivity.

Here’s an overview of what to look for when making the business case for investment in VoIP technology for a VoIP PBX solution:

• Eliminate or reduce intra-office toll charges
• Avoiding service and support contracts on existing PBX hardware
• Eliminate the need for ongoing Centrex services and charges
• Reduce expansion costs via lower costs for adds, moves and changes; lower user hardware costs
• Reduce the ongoing costs for separate voice messaging systems
• Provide productivity benefits for remote and traveling workers who can be empowered with the same integrated capabilities as office workers
• Reduce user training and learning on phone and messaging systems
• Cost-effectively implement unified messaging
• Improve security
• Reduce systems downtime and improve performance

How Does The Solution Work?

Inter/Intra office calls

Caller A, who is located in the corporate headquarters, wants to make a call to Caller B, who is located in the corporate headquarters or in any of the company’s offices worldwide.

Caller A picks up his VoIP device (IP phone, phone with adapter or softphone) and dials Caller B’s extension.

The VoIP PBX server searches its internal database and obtains call routing information about Caller B The VoIP PBX server routes the call to Caller B’s VoIP device.

If the destination number is unreachable, the system forwards the call to Caller B’s voicemail.

As soon as Caller B picks up his VoIP device the conversation starts.

During the conversation Caller A’s VoIP device convert voice to digital packets and send them to Caller B’s VoIP device and vice versa.

Both A and B can use traditional PBX functionality, like call on hold, caller ID, call forward, etc. Calls are free

Outbound calls

Caller A, who is located in the corporate headquarters, wants to make a call

to Caller B, who is a company customer.

Caller A picks up his VoIP device (IP phone, phone with adapter, or softphone) and dials the customer’s number.

The VoIP PBX server searches its internal database and obtains call routing information about the VoIP carrier, who should terminate calls to Caller B’s area code.

The call is routed to the VoIP carrier.

The VoIP carrier terminates the call to Caller’s B number over the PSTN.

During conversation, Caller A can use traditional PBX functionality, like call on hold, caller ID, call forward, etc.

Calls are charged on time basis at pre-negotiated rates with the VoIP carrier

Inbound calls

Caller A, who is a company customer, wants to make a call to Caller B, who is a company employee.

Caller A picks up his phone and dials the company’s central access number.

The VoIP PBX server prompts the caller to enter an extension.

Caller A dials Caller B’s extension.

The VoIP PBX server searches its internal database and obtains call routing information about Caller B.

The VoIP PBX server routes the call to Caller B’s VoIP device.

During conversation, Caller B can use traditional PBX functionality, like call on hold, caller ID, call forward, etc.

Calls are either free if the company uses a local access number or charged on a time basis if the company uses a toll-free one.

Voice over IP (VoIP) technologies carry great promise to reduce telecommunication and networking total cost of ownership while empowering businesses with new capabilities and agility. When making your decision on deploying a Virtual Office VoIP PBX solution consider the strategic and tangible benefits as well as the costs and risks outlined above. If it all seems too overwhelming just let Firepair Consulting design and implement a system that’s right for you and your company.

Recommended Reading for People Who Are New to the Field

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• C. E. Perkins, Ad Hoc Networking. New York: Addison-Wesley, 2001.
• S. Ramanathan and M. Steenstrup, “A survey of routing techniques for mobile communications networks,” Baltzer/ACM Mobile Networks and Applications, vol. 1 (1996), pp. 89-104.
• E. M. Royer and C.-K. Toh, “A Review of Current Routing Protocols for Ad Hoc Mobile Wireless Networks,” IEEE Personal Communications, 1999, pp. 46-55.

Conclusion

Besides the public (mobile) operators, the introduction of dedicated networks has spawned private network operators. Examples are the GSM-rail, TETRA, and WLAN hot spot operators, and military networks. Most of these operators ask for turn-key solutions from their vendors, hence the need for simulations is more or less absent. The defense departments are an exception to this rule. Since they want to be sure that their networks can be operated in extreme conditions, they run extensive network simulations to prove this [6].

Like with the public mobile operators, testing equipment under realistic and extreme conditions is the major perspective shift compared to standard simulations. This perspective adds the following conclusion to the previous ones:

• The use of parallel computing for radio network simulation is still in its infancy, especially when compared to other industries.

As early as 1996, Weiser & Brown talked about the ubiquitous computing era (UC era) in which “we will have lots of computers sharing each of us. Some of these computers will be the hundreds we may access in the course of a few minutes of Internet browsing”. The ‘calm technology’ that Weiser and Brown envisioned has today become a reality thanks to wireless networking (1996). Wireless technology has become the ‘buzz word’ in recent years, with wireless networking becoming more available, affordable, and user-friendly. Recent advances in the fields of modulation techniques, coding, and radio architecture are allowing wireless communications to have large speeds, better spectrum allocation, greater power efficiency, error-resistant transmissions, and more flexible architectures. Technically speaking, these advances permit complex transmitters and receivers to pack more bits into the same spectrum by using a wider slice of the spectrum (ultrawideband), a more narrow set of frequency bands (orthogonal frequency-division multiplexing), more directional use of spectrum (smart antennas), and more intelligent encoding of transmissions (coding). In addition to higher bit rates, more flexible radio architectures are also part of the advancing wireless technology.

Wireless technology is used in three main areas: Wireless LANs for pure data applications; Wi-Fi networks used to enable both data and specialized applications (RFID, location services, and especially VoIP); Wide-area mobile data access for PDAs, notebooks, and smartphones using Wi-Fi, 3G and/or GPRS.

There are two recent modulation techniques that have changed accelerated the popularity of wireless technology – ultrawideband (UWB) and Orthogonal Frequency-Division Multiplexing (OFDM). UWB is any wireless technology where the signal is 25% or more of the frequency used. UWB has wideband nature, consumes very little power, and is economically cheap (Heller, 2006). In the book “Computer Science: Reflections on the Field, Reflections from the Field,” Mark D. Hill has said that technological progress will always enable better and cheaper computers (CSTB, 2004). Ultrawideband technology, offering a solution for the bandwidth, cost, power consumption, and physical size requirements of next-generation consumer electronic devices, is definitely indicative of technological progress.

Other knowledge advances in various realms related to wireless are:

• Orthogonal Frequency-Division Multiplexing (OFDM) is a technique in which a single transmitter transmits on different orthogonal frequencies. It provides spectrum efficiency with high resistance to interference (Heller, 2006).
• Multi-antenna systems or smart antennas refer to multiple receiving and/or transmitting antennas. Smart antennas enable performance gains in four areas: array gain, diversity gain, spatial multiplexing, and interference reduction (Heller, 2006).
• Space-Time Codes and Turbo Codes (TCs) help to pack more bits into the same bandwidth. Turbo Codes are high-performance error-correcting codes that are good choices for limited-bandwidth, high-noise communications. They can increase the usable bit rate of a signal without increasing transmission power (Heller, 2006).
• Software-Defined Radio (SDR) is a technique meant to enable fast, flexible switching between different frequency bands (Heller, 2006). Two popular applications of wireless information systems are GPS and RFID. The Global Positioning System (GPS) is a wireless technology-based system used for location awareness. Radio Frequency Identification (RFID) tag is one in which individually programmed RFID tags, or transponders, use radio signals to capture and share data between mobile and fixed computing devices, allowing automatic data capture and object identification (Raychauduri, 2005). The global industry and business are currently working towards implementing RFID tags throughout the entire supply chain.
• Wireless Personal Area Networks refer to small ad hoc networks and have a limited range. Recent advances in WPANs include Bluetooth wireless technology.
• WiMAX (World Interoperability for Microwave Access) technology is expected to enable true broadband speeds over wireless networks at a cost point to enable mass-market adoption. WiMAX is the only wireless standard today that has the ability to make pervasive connectivity a reality (Moore, 2006).
• The third-generation CDMA-based 1x technologies allow for high-speed data and enhanced voice quality and capacity over CDMA networks. These technologies promise to take users into a new realm of mobile computing, ranging from receiving and sending e-mails to watching streaming videos or even attending a video teleconference (Moore, 2006).

Pervasive computing is the next generation computing environment with information & communication technology everywhere, for everyone, at all times. As early as 1976, Newell writes that someday, computer technology may incorporate intelligent behavior into objects (CSTB, 2005). We can create “frozen action to be thawed when needed,” and the action can be conditional on the state of the world. In accordance with the above visionary statement, Prof. D. Raychaudhuri says that wireless systems are evolving from today’s centrally managed cellular and WLAN services towards ad-hoc heterogeneous networks capable of supporting a broad new class of “pervasive computing” applications (Raychauduri, 2005). Enabling technologies for this pervasive computing scenario include infostation (wireless cache), multimodal wireless sensors, self-organizing ad-hoc network protocols, and cognitive radio (Raychauduri, 2005). In just five years, Raychauduri believes, networks of embedded devices will be all around us (Raychauduri, 2006).

As wireless networks are shared, management and security are two major issues to be considered. With certain LAN standards (of good bandwidth), a license is needed to operate. Wireless devices are sometimes susceptible to interference from other devices such as cordless phones that also operate in the same frequency band. Even Bluetooth devices sitting in close proximity can cause interference. The wireless medium is time-division multiplexed, meaning a client can either send or receive data at a time, but not both, and moreover, the actual transmission rate is dictated by physical factors like indoor settings and the quality of equipment used. Since a wireless network uses shared bandwidth, the throughput reduces as the number of clients increases. Security could be an issue in a wireless environment, as anybody in the vicinity can try to hack into the access point.

Some other problems to be overcome are data integrity, speed, protection, compatibility, and environmental safety (Eremin, 2005). A more serious drawback is that standards are lacking in wireless networking, which is why very few wireless products can work with one another (Eremin, 2005).

Bibliography

1. “Future Directions in Wireless Technology” by Prof. D. Raychaudhuri, February 2005, SUNY Stony Brook. Download PowerPoint presentation
2. Alexei A.Eremin, (2004) Effects of wireless computing technology. Pushkin Computing College.
3. Computer Science and Telecommunications Board (2004). Computer Science: Reflections on the Field, Reflections from the Field. National Academy of Sciences Press.
4. Heller, Brandon. The Quest for Wireless Gigabit: Recent Advances in the Wireless Physical Layer. 2006. Web.
5. Mark Weiser and John Seely Brown (1996). The Coming Age of Calm Technology. Xerox PARC.
6. Moore, K. Linda (2006). Wireless Technology and Spectrum Demand: Advanced Wireless Services. CRS Report for Congress. Web.
7. Raychauduri (2006). Pervasive Wireless. Technology Review – published by MIT. Web.

Introduction

Wireless network is a common trend that business organizations are adopting with the intent of providing multiple access points to their clients and employees. There are a significant number of operational advantages associated with wireless networks such as eliminating the need to deploy cables for client workstation and hence reducing the costs associated with setting up and expanding the network.

In addition, most computing devices in the present age have an inbuilt Wi-Fi sensor, resulting to its widespread. There are also a number of limitations associated wireless networks, for instance the inconsistencies in frequency ranges of broadcasts and operational limitations, security issues and many other limitations.

This implies that before an organization embarks on the deployment of wireless networks, it is important to analyze critically the offset between the limitations and advantages of wireless security networks^[1]. This paper provides an analysis case study in Australia concerning the security issues during the deployment of wireless networks for organizations and overview of the effect of “war driving” and ‘war chalking” on the uptake of wireless networks in Australia.

Risks of using wireless networks and how they can be overcame

Research study by McAfee reveals that 50 per cent of wireless networks in Australia face immense security issues, and that 60 percent of large business corporations have no security implementation measures on their wireless networks. There are risks issues associated with using Wi-Fi at home or in the business organization.

The most common problem associated with Wi-Fi is bandwidth stealing, whereby unauthorized users try to use the wireless network access points. In addition, wireless transmission can face interception that can go undetected. The most critical vulnerabilities that wireless networks are susceptible are eavesdropping, unauthorized access, and denial of service^[2].

Wireless networks propagate their traffic through air; this implies that there are no methods to control recipients of the broadcasts, because they use an unguided transmission system. As a result, wireless network is prone to interception by third parties. In order to curb this threat, it is imperative that wireless networks should deploy encryption when transmitting their stream.

The second risk and vulnerability associated with wireless networks is the nature of the protocols deployed in them. The protocols used in wireless network makes the network to be user friendly because it has weak authentication methods.

Most laptops and mobile devices have the ability to detect the presence of a wireless network since an access point to a wireless network broadcasts a network name. This means that if access to the network has no restrictions, a client sensing the broadcast is likely to gain access, since a significant number of network administrators do not implement access levels to their wireless networks.

A wireless network is prone to denial of service attacks whereby an attacker hacks into the network with the aim of rendering the network unusable to its legitimate clients. Attacks such as the “ping of death” can crush the wireless network servers to crash.

Denial of Service attacks are more effective in wireless networks because such signals travel in the public domain rather than guided cables, making it difficult for network administrators to detect and prevent such attacks. In addition, wireless networks are subject interference from nearby radio transmissions. There is possibility that accidental interference is likely to occur due to the close range of frequencies assigned to wireless networks.

Securing a wireless network from the above requires effective planning through analysis of the possibility of any interference as a resulting the frequency of broadcasting or interception. An important strategy is to implement access controls to the network to limit the number of people who can access and use the network. Encryptions serve to code that data transmitted via wireless networks such that even a person can gain access to the data stream, one can make a meaningful use of the data on the network.

Threats can also combated by using static IP addresses on the devices that have the right to access the network. In addition, an organization should deploy firewalls and network security applications that serve to identify the allowable access points and reports any additional access point that is not allowable on the list of static IP addresses assigned to MAC addresses of the hardware on the network^[3].

Effect of “war driving” and “war chalking” on the uptake of wireless networks in Australia

War driving bases on the concept that it many operating systems such as windows makes it easy to detect wireless networks that are broadcasting in a given frequency range.

This means that roaming users can easily detect and access unsecure wireless networks. The relative ease by which users can detect wireless networks is what is called “war driving”. War driving has increased the people interest in driving around with the aim of locating and accessing wireless networks that require no authentication. In Australia, there are vast unsecured wireless networks, hence drawing user to map unsecure access points.

War driving is further enhanced by the fact that there are online utility software to aid in the detection of such wireless networks by laptops and mobile devices such as the PDA. In addition, the availability of many unsecured networks is one the most significant driving factors behind war driving. For instance, McAfee marketing directors reports that out of 622 networks found in Sydney’s North shore, 29 percent of these networks had no security implementation at all.

In residential areas such as the Neutral bay, he reports that 42 percent of the networks had no security measures, while those that attempted to implement security were using the older version of Wired Equivalent Privacy (WEP). This older version is prone to hacking, thereby facilitating unauthorized access by malicious users to the private and public wireless networks. This implies that war driving has had a significant effect on the security risks of wireless networks in Australia^[4].

War chalking on the other hand refers to openly marking places that are access points to public wireless networks. War chalking is not common phenomenon in Australia because individuals who discover public access points are not willing to make it known that the area is an access point to a vulnerable wireless network.

Majority of individuals in Australia go out for war driving as a hobby, with the intent of collecting and pinpointing hotspots. The challenge to owners of vulnerable access points is that they cannot determine the attacker or the person who is responsible for jamming the network. In addition, network administrators have the challenge of determining whether a user is war driving for fun for the sake of a free connection or a attacker who aims at stealing information and rendering the network vulnerable.

This means that it makes it difficult to evaluate and implement security measures to such networks since most of them serve to attract clients to a business premise such as a hotel. However, the underlying requirement is that networks in Australia need to remain secure in order to avoid threats associated with war driving and war chalking.

Issues of security and privacy that organizations must consider when adopting a wireless network

Implementing a wireless network means that one is creating multiple access points to the network since there is no method for controlling the transmission of wireless networks. With regard to this, organizations have the need to implement the security and privacy policies regarding the ways in which the users can access the network. Implementing wireless security implies that the organization deploys various strategies aimed at limiting access to wireless networks^[5].

Some of the security and privacy issues associated with unauthorized access that organizations must put into consideration include accidental association, malicious association, ad hoc networks, identity theft, and man-in-the middle attacks. In addition, there are security concerns regarding attacks such as Denial of Service attacks, network injection and Caffe Latte attack.

Accidental association is due the overlapping between wireless networks, making a user in such a hotspot a link between the two company networks. Malicious association on the other hand takes place when an attacker uses the network’s access points to impair the functionalities of the network and steal information.

Ad hoc networks are also a security concern in wireless networks because they tend to link two wireless networks in a peer-to-peer manner. Other attacks such as wireless network intrusion are a form of security threats that the organization must develop strategies to counter them.

Threats posed by war driving and war chalking to wireless networks

Despite the fact that most people on war driving and war chalking are undertaking it for the fun of enjoying a free wireless connection, some are some unscrupulous users who might this advantage to attack the network, as a resulting posing security threats to the network.

Depending on the knowledge of the user, one can pose a serious threat to the security of the network. There are diverse ways through which people on a war drive can use their knowledge to affect the security of a wireless network. For instance, a person can use his network security and cryptography skills to decrypt the contents of data stream in the network, thereby posing a threat of information theft to the organization.

People having a networking expertise can ping wireless network to obtain critical information concerning the configuration of the network, depending on their motives, they can initiate a denial of service attack or crush the whole network down by changing the configuration since most unsecure wireless networks have no access control strategies. There is also a possibility that people on war drive can bypass the firewall and access the organization’s critical information.

Issues to put into consideration when running free Wi-Fi services

Running free Wi-Fi services is a new trend that business enterprises are embarking on with the aim of attracting customers to their business premise. It is important for such businesses to put into consideration the security concerns associated with free Wi-Fi services, since it is difficult to ascertain the motive of the network user.

One strategy to ensure this is to facilitate the issuance of static IP addresses to users so that their activities on the network are traceable. Security applications such as proxy firewalls need to be implemented to the wireless network to enhance security^[6].

Wireless network security application software

There are a number of applications used for tackling wireless network security issues. Some of them include Wi-Sentry version 4.2, Wi-Fi gear, and Wi-Fi Guardian. Wi-Sentry version 4.2 functions by performing a behavioral analysis and detection of devices that gain access to the wireless network. Therefore, Wi-Sentry ensures wireless network security through monitoring the access points in a network for rogue behaviors and ensuring that only authorized users get access to the network.

Wi-Fi guardian on the hand is utility software that aims at enhancing security to a wireless network. Some of the features of the software include high encryption, a client can surf safely in unsecured wireless networks, and a client in the wireless network is anonymous and not visible to other users in the network and an additional online server support with 100 percent availability. The software goes for $50 subscription annually.

The iOpus Private Internet Gateway is also wireless network security software (IPIG) that uses encryption to enhance security. The IPIG also fosters security through creation of a secure tunnel that aims at protecting a user’s communications bounds such as email and FTP in a wireless network. The IPIG is an open source application, meaning it is available free and its code can be modified.

Bibliography

Earle, A,. Wireless security handbook, Auerbach,New York, 2005.

Merritt, M., Wireless security, McGraw-Hill Professional,New York, 2005.

Randall, N., Wireless security: models, threats, and solutions, McGraw-Hill Professional, New York, 2002.

Footnotes

1. A Earle, Wireless security handbook, Auerbach,New York, 2005. Pp. 56-58.
2. A Earle, Wireless security handbook, Auerbach,New York, 2005. Pp. 60-64
3. M Merritt, Wireless security, McGraw-Hill Professional New York, 2005. P. 67.
4. M Merritt, Wireless security, McGraw-Hill Professional New York, 2005. Pp. 78-90
5. N Randall, Wireless security: models, threats, and solutions, McGraw-Hill Professional, New York, 2002. Pp. 67-70.
6. M Merritt, Wireless security, McGraw-Hill Professional New York, 2005. Pp. 78-90

Abstract

Fire fighter and other rescue personnel who have to use the radio harness to hold their radio often face a problem when the belt holding the radio and the mic starts swaying away from the body. This can create further problems as the personnel would be forced to use one of their hands to restrain the radio and it creates an issue of personnel safety. The Boston Leather Radio Strap is designed to hold the radio close to the body and save the personnel from such issues. This paper analysis the device to understand its benefits. The conclusion offered is that in spite of the higher acquisition costs, the Boston Leather Radio Strap should be recommended for use.

Why Boston Leather Radio Strap

According to a report by Associated Press (October 08, 2007), some 15 firefighters have died in the last year because some of the safety devices they used did not function properly. Also included in the report is the problem faced by firefighters when they are climbing ladders or dragging fire hoses into burning, smoke filled buildings. One of the main support systems in such events is communication with team members through radio. Firefighters have only two hands that they must use to hold the fire fighting equipment. While fighting fires and when the operator is not standing straight, the radio strap tend to sway this way and that and firefighters have to reach out with one hand to pull the radio close so that they can speak. When this is happening, one of their hands is otherwise engaged and there is a severe possibility that the operator would get injured while fighting the fire and risk his life. There is also the possibility that the swaying radio strap along with the radio may get entangled and trap the firefighter. In such cases, there is an urgent need to ensure that the firefighter is free from these problems. The Boston Leather Radio Strap helps to prevent the sway of the radio strap away from the body.

About the Boston Leather Radio Strap

The Boston Leather Radio Strap (Boston Leather, 2008) is a device that holds is the safety device that mates to a radio holder with rust free scissor snaps for easy removal. The radio holder device has to be purchased separately. The strap is available in heavy-duty leather of 1 1/4″ width and it is provided with a reflective backing for extra safety. The buckle locking is positive and allows clamping and removal easily. Shown below is an image of how the device appears.

There is another unit called the anti-sway strap that actually fits to the gear and stops the radio from swaying and swinging around. An image of the device is as shown below.

The length of the strap can be adjustable and for taller fire fighting personnel who are more than 6’1”, the item is manufactured in extra large size. The speaker microphone is attached to a leather loop so that it can be accessed easily. The strap can be fitted in over any of the shoulders. The buckles, hooks and eye bolts are made of high temperature resisting Nickel. The devices are lightweight and weigh less than 1 pound.

Survey of preferences for the belt.

A poll was done to assess the user acceptance of the device and among 100 fire fighting personnel. The personnel was asked for reasons as to why they would like to use the device. Among the 100 people polled, 67 people said that they liked the device while 20 said that they did not like the device. 13 people said that they had no comments about the device or that they did not care. The results of the survey are shown in the following graph.

As seen in the above figure, 67% of the respondents have agreed that the device is useful and would be ready to accept them. Among the reasons for liking, the respondents have suggested:

• Ease of caring for product
• Holds radio microphone in place
• Slides easily over turnout gear
• Keeps radio knobs reachable
• Keeps radios from falling on the floor

Disadvantages of the device

It is reported that the device costs between 40 to 50 USD and there is also an adjustment period that some of the people did not like.

Conclusions and Recommendations

The discussions in the paper have shown that the Boston Leather Radio Strap has many advantages as it can save personnel from injury and protect the radio from being damaged. There are also some benefits such as Ease of caring for product; Holds radio microphone in place; Slides easily over turnout gear; Keeps radio knobs reachable and Keeps radios from falling on the floor. The only issues is the cost of the strap that is about 40 – 50 USD. A survey showed that 67% of personnel liked the product while only 20% did not find it acceptable.

Considering the life and safety of the fire fighter that is irreplaceable and the cost of the radio that costs much more than the 40-50 USD of the strap, it is recommended that the Boston Leather Radio Strap be purchased and can become a part of the regular attire of the firefighter.

References

1. Associated Press. 2008. Safety device may be linked to firefighter deaths. Web.
2. Boston Leather. 2007. Firefighter’s Radio Strap.

Thesis Statement

This paper will review the ideas of other authors on multitasking when using given technological devices. It will be based on observations drawn from how people try to switch from different technological devices either to keep in touch with peers, listen to music or follow certain programs on TV. Due to changes in lifestyles and technological innovation, present day life calls for the ability to handle more than one activity at the same time in order to accomplish more tasks within the same time. Lack of this ability could make people fall behind.

This paper establishes that it is easier to multitask when using given devices than when using others. Multitasking e.g. speaking on phone while crossing or driving has been linked to many traffic accidents; a person talking on phone may engage his or her mind fully to the conversation and forget all about the oncoming motorists (Goodall et al, 2009). Therefore, understanding what devices to use and how it affects other operations is very important.

Why People Multi-task

There are two basic reasons why people multitask. For instance, individuals multitask because what they are currently doing is not interesting any more or because they expect new information from the other channels. Ophir et al (2009, p.5) suggests that this behavior is more prominent among young people and attributes it to “attraction to new information.”

A few older people who multi-task are in the habit because of the urge to switch between old information and new information. This habit, it’s argued, is slowly causing people to develop dependency to machines. Ophir et al (2009, p. 3) assert that the habit will make “people lose empathy as most of the time they are stuck to digital devices looking for information.”

There are two opposing arguments about multitasking; one supports multi-tasking pointing out that the practice improves our social links (Goodall et al, 2009, p. 57). The second school of thought is opposed to multi-tasking based on the fact that it reduces direct human interaction.

The instant messenger on the blackberry for example is thought to be an addictive practice that and may not allow one to multi task well. Dependence can also result from repeated use of other digital devices such as; ipads and Bluetooth (Goodall et al, 2009, p. 64). There is a craze to have the most modern communication technology gadget. However, considering the impact of the different gadgets on an individual, it is important to approach new gadgets more cautiously.

When the internet became the new way of doing things, many people jumped at becoming e-savvy. However, Wilkinson (2008, p. 23) shows the bad impact of new innovation has on personal life and interpersonal relationships. Wilkinson (2008) points out that on the onset of internet, some men became more married to the internet than to their wives.

Due to new gadget and internet taking over people’s time, many marriages are strained (Wilkinson, 2008, p. 38). This case alone is not conclusive i.e. one cannot use it to term use of all new innovative gadgets as harmful. Other internet users, Wilkinson (2008) further explains, have registered that the internet enhances their personal and even marital relations through instant messaging, emails and chats.

The fascination with instant messaging, enabled by devices like the blackberry, leads to individuals getting too engrossed to an extent that individuals may not realize or what is going on in their immediate environment or surroundings. When one is chatting with another via instant messaging on a blackberry, there is pressure or demand to write back in answer to the person on the other side quickly.

One also feels pressured or the need to compose the best questions and answers thus getting really engrossed. The action becomes even more engrossing or draws one to oneself even more when one is chatting or interacting with more than one person.

Since the blackberry presents a channel through which one can access a lot of information of varied nature, than other digital device such as a radio or television, the level of multi-tasking when using it is lower than say when one is relying on other devices like the radio or TV for information or entertainment.

Just like in the case of drug addicts, Ophir et al (2009) points out that the human brain if exposed to a constant flow of information from an electronic device develops tolerance to this flow. If the flow is stopped, the mind triggers a signal to seek for more information. This is what happens to somebody using instant messenger on a blackberry. The same person becomes interested to follow a program either on radio, TV or listen to music from a Bluetooth.

Wilkinson (2008) is in agreement with Ophir et al (2009 and points out that instant messaging on a blackberry limits what one can engage in at the same time. Multi-tasking is near impossible when one is using gadgets like the blackberry because the human mind has limitations on what it can do.

He emphasizes that the human mind responds voluntarily to the information available in the surroundings. It is important to seek for the equilibrium in this scenario so as to avoid being addicted to practices like instant messaging. The best way to do this, Tyson and Cooper (2010) suggest, is to switch off the media that is a source of novel and exciting information e.g. the blackberry for some time. It is important to disconnect the brain from the flow of the information for some time to give it a break.

Conclusion

Research, as discussed by Ophir et al (2009), indicates that human beings have a tendency to drift towards forms of powerful technologies. The blackberry being one of the powerful communication gadgets of our time pulls or glues many people.

The radio and TV have been there for some time; we have interacted with them and are tired of them. Another digital device more powerful than the blackberry may render the blackberry less usable again. However, as people take to new gadgets, it is important for them to appreciate how all the new gadgets affect them.

Reference List

Goodall, S., Goodall, H. L. & Schiefelbein, J. (2009). Business and Professional Communication in the Global Workplace. 3^rd Eds. London: Cengage Learning

Ophir, E., Nass, C. & Wagner, A. D. (2009). “Cognitive Control in Media Multitaskers”. Proceedings of the National Academy of Sciences, PNAS, 106 (33), 1-5

Tyson, J. & Cooper, A. (2010). How Instant Messaging Works. Retrieved from https://computer.howstuffworks.com/e-mail-messaging/instant-messaging.htm

Wilkinson, K. (2008). The Happiness Factor: How to Be Happy No Matter What! Texas: BookPros, LLC

Outline

This paper primarily aims to give a better understanding of Radio Frequency Identification. RFID’s have spread their wings around the globe, and their benefits are numerous.

The paper first talks about how they have saved businesses money and time in managing their assets and inventory and how they have become dynamic substitutes to barcodes over the period.

Secondly, the paper talks about the vast impact RFID’s are having on companies and industries, how they are being used for various purposes in different industries and how these industries have benefited from them.

Lastly, the paper talks about the importance of integrated RFIDs. Since companies are now interlinked together and also work together to achieve common goals, RFID’s should be implemented across the supply chain to achieve the greatest efficiency and accuracy.

Based on your background readings, what makes RFID such a big deal in managing production and inventory?

Ans1. RFID is a major player in the field of production and inventory management. The systems based on RFID provide a piece of accurate information related to product and inventory levels at thousands of firms and retail outlets across the globe. Production and inventory systems start from the factory or supplier and end at the retailer. RFID provides an end-to-end supply chain through which every single product is monitored and controlled from production till it reaches the consumer.

RFID has become a dynamic substitute for bar codes in many places. All this hype has various reasons to it; RFID systems are powerful, compact, flexible, and can carry extensive amounts of information regarding products and inventories. The use of state-of-the-art wireless technologies is used to track products, inventory, and even equipment in a flawless manner. RFID provides a platform for businesses to engrain a fully automated data securing and analysis system that helps businesses keep track of their resources, whether it be inventory at a cell phone manufacturing company or a fleet of vehicles for a flower delivery firm. Where optically based systems lack, RFID provides logical solutions to various logistical problems. As compared to bar codes, RFID’s do not require a line of sight, have an extensive and portable database, tracking is conducted in real-time, and multiple tags can be read/wrote simultaneously.

Moreover, RFID technology, although being the latest, is still evolving and becoming more affordable. New innovations are also coming up, for e.g., a weather and traffic update system for truckers and delivery vehicles. This would enable them to avoid heavy traffic and re-route as per weather and traffic conditions. Therefore, RFID is a very effective and efficient system, and companies worldwide are using these systems to work towards their goals, including tracking and authenticating valuable assets, managing aviation baggage handling, manufacturing processes, etc.

What is the nature of the impact that RFID is having on industries and on individual companies within those industries?

Ans 2. RFID has a major impact on various industries and their respective individual companies in a variety of ways.

The benefits are reaped excessively by the retail industry, for e.g., the German retailer Metro which has thousands of different products, RFID tags are used to monitor inventory flows, deliveries, expiry, etc. The transport sector uses RFIDs to track vehicles, trucks, aircraft, etc. For e.g., the system enables cars to be tolled on various roads automatically using the transponders and receivers attached to the respective roads and vehicles. In agriculture, RFID is used to track the movement of animals, their health, age, and various other data. Almost all manufacturing industries ranging from pharmaceuticals to textiles are using the technology to streamline their processes, eliminate redundancies, control and monitor inventory, production, and also processes. RFID is also particularly important in the distribution sector; it provides visibility at all levels, eases registration processes, improves accuracy and authenticity. RFID is also swiftly entering the aviation, consumer applications, security, healthcare, and transport sectors.

All in all, RFID impacts all industries in a positive manner. It saves sales personnel expenses and the time to check inventory repeatedly by eighty percent, and it provides greater authenticity and accuracy complemented by reduced costs and operational productivity. It also provides emphasis on accurate and updated expiry dates, lot and batch tracking, and improved returns management infrastructure. At the operational level, operational productivity is enhanced, shipping is monitored and controlled, and receiving accuracy is also guaranteed. Moreover, product and consumer security and safety issues are also addressed. RFID supports anti-counterfeiting measures and theft or shrinkage management. As a result, the cost of goods sold is decreased considerably, and the improved asset and inventory utilization can have several beneficial results on company financial statements.

Given the current, rapidly changing logistics environment, to what extent do you think a company can afford to “go it alone” when making choices about managing its inventory and production?

Ans 3. As per the question, given the current, rapidly changing logistics environment with extensive collaboration between suppliers, distributors, and retailers in the form of networking and various other linkages, it would be unfeasible for a company to “go it alone” when making choices about managing its inventory and production.

Although many successful RFID pilots are used by single companies, with no collaboration with other supply-chain partners, the full benefits and returns can only be realized when all the different supply-chain partners work together. This is the primary reason why large retailers such as Wal-Mart are encouraging suppliers to implement RFID. Thus, RFID’s value is realized only when companies work together in the form of information sharing, analysis, and joint decision making.

References

1. Lauren R Hartman. (2005). RFID in the consumer goods supply chain. Packaging Digest.
2. Patrick M Bryne. (2002). Supply Chain RFID: Lessons from a leader. Logisitcs Management.
3. Patrick M Bryne. (2002). RFID: Not just for Wal-Mart. Logisitcs Management.
4. Shepard Steven. (2005). RFID Radio Frequency Identification. Illustrated. Mc-Graw Hill Professional.

Introduction

Radio development entails movement from wireless telegraphy to more advanced ways of programming. Many people have contributed to Radio development with Edwin Armstrong being the most credited for advancing many features of the Radio. Edwin Armstrong was born in the year1890 in the city of New York. He was a student in the University of Columbia and upon completion of his training; he became a professor in the same university. Armstrong has had a profound influence on the Radio and his inventions have affected the media, especially the Radio. He was among the pioneers of the broadcasting industry and was passionately dedicated to the enhancement of radio technology (Dominick).

Discussion

Armstrong initiated three significant innovations that have improved the presentation of performance in today’s Radio. The three inventions include rejuvenation, super heterodyne circuit and finally, the wide-band FM (Frequency Modulation).

The year, 1912, marked his first innovation known as the rejuvenation or feedback circuit. The circuit involved passing received radio indicators through a radio pipe for almost 20,000 times in a second. This increased the energy of the received radio indicators and enabled radio broadcasts to have a broader range. It also improved wireless radio information transmission since it could intensify weak radio indicators without alteration. Rejuvenation, which Armstrong defined as the use of positive response, increased the frequency of received radio indicators to the extent that they could be recognized without headsets. It thus proved more efficient compared to the radio receivers of that era.

His services as a radio officer resulted to the initiation of the super heterodyne circuit. The invention enabled radio listeners to obtain information from distinct radio stations. The innovation and development of the circuit also made radio receivers, the chief communication tools of the time, more susceptible and selective. Before the circuit’s discovery, radio indicators often superseded and meddled over one another and this made them ineffective. The circuit thus made radio receivers simpler to use, and this replaced the long process of tuning controls on radiophones. This technology is still beneficial in the contemporary society.

The super heterodyne circuit as invented by Edwin Armstrong made use of heterodyning to translate received radio indicators to a predetermined intermediate frequency, which could be easily processed as opposed to the former radio transmitter frequency. Armstrong invented the circuit as a way of overpowering the deficiencies associated with the use of early triodes. This was different from the early radio transmission, which was only focused towards making transmitted signals perceptible.

Unlike old radio circuits, which are only involved in making received signals clear, super heterodyne circuits determine the strength of transmitted signals and this leads to linear improvement in the real carrier wave. Armstrong’s super heterodyne receivers have effectively substituted former receiver designs. The circuit provides greater sensitivity, constant frequency, and selectivity. When compared with other circuits such as the Tuned Radio Frequency Circuit (TRFC), super heterodyne circuit provides greater stability since an oscillator is more easily recognized than an amplifier. The circuit also operates at low amplitudes and can thus provide confined pass bands when compared to TRFC circuits. However, the circuit is difficult to operate and thus needs high-qualified personnel.

In 1917, Armstrong continued with his efforts of making long distance dissemination of information feasible. It is during this time that he discovered the “Super heterodyne circuit,” which enhanced the capacity to receive radio indicators thus allowing for better selectivity and intensification. This is mostly applied in the contemporary society where after switching on a Radio, one expects his favorite station to play first. This is different from the past where fading and static radio problems were common especially in local radio stations. During these days, the notion of automatically switching on ones favorite radio station was impractical.

Through Armstrong, radio listeners can choose a particular station and play it loudly so that they can have maximum fun. The super heterodyne circuit also made the functioning of Radio receivers simpler by eliminating the usage of various tuning controls. This has made modern Radios more susceptible and selective (Dominick).

Armstrong’s radio contributions were enhanced through the fact that he was never contented with his early innovations. He, therefore, always sought to advance them. For instance, while his innovation of the rejuvenation circuit played a big role in the early radio, it had one disadvantage. The circuit had a static disadvantage in that it augmented both radio and interference indicators. These became severe in the summer when mechanical storms developed “static seasons” as described by radio operators. As a result, Armstrong became dedicated to eradicating stoical problems in radio response though this took him a lot of time.

In 1933, Armstrong’s attempts improved the broadcasting technology. He invented the FM band, which substituted the AM band. Early radio stations were made up of AM stations. During this time, Radio listeners could only listen to two broadcasting stations, that is, NBC and CBS. The stations were subject to several kinds of atmospheric destruction. Indeed, some newspaper articles of the time had a predictor on the radio page to assist listeners in forecasting how stations would follow each other.

Armstrong’s FM innovation solved all the problems associated with the AM. For instance, the frequencies of FM waves stay constant and this has made FM more resistant to noise since differences in frequencies of FM waveform can be eradicated in its receivers by devices known as amplitude limiters. In FM radio indicators, much energy is found in its sidebands while in AM wave bands, a small portion of the total power is found in its sidebands with much of it being exploited in the carrier. In FM radio systems, the power of broadcasted indicators depends on the frequency of the uncontrolled carrier indicators and is therefore constant. This is different from AM systems where transmitted energy depends on the amplification index. As a result, FM is more advantageous than AM since its mode of information transmission is quite clear.

FM’s wavelength is short and the amplitude is high. As a result, FM is not affected by activities caused by man such as traffic jams or even activities with natural origins. Information passed through FM radio stations is susceptible to minimal distortion. This is because the waves are less vulnerable to obstructions from buildings and other human activities. Since FM radio operates at high frequencies, it carries more data compared to AM radio, which operates at low frequencies.

It should further be noted that FM waves have low radiated power and well defined regions for a specific transmitter power. The development of the wide band FM has provided Radio listeners with a dynamic experience, better sound features, and conformity compared to the Amplitude Modulation (AM). Armstrong’s invention of the wide band FM was quite momentous. FM enabled the diffusion and clarity of a broader range of acoustic frequencies compared to AM. It further solved the problem of static audio, which was a major problem facing the AM.

Armstrong’s Radio inventions have led to the current electronic technology operating in Radios. His innovations revolutionized Radio communications and are still in use in the modern Radio performances. Armstrong also invented the “Lee De Forests Audio.” In his research, he realized that the device would undulate upon increase in Radio response. As a result, the device could not only recognize and intensify radio signals but could broadcast them as well. His study and experimentation with the AudioNet improved radio reception and the functioning of spark gap transmitters. Radio indicators were improved through rejuvenation to the extent of human hearing without the usage of headphones.

Conclusion

Armstrong’s inventions are very influential in the modern radio technology. Research shows that his three major innovations, that is, the rejuvenation circuit, the super heterodyne circuit, and the wide band FM are crucial components of nearly all modern telecommunications internationally. His innovations, therefore, have formed the basis of modern radio technological advancements. He is, without doubt, the founding father of the broadcasting industry and thus deserves respect from the contemporary society.

I feel that Edwin Armstrong stimulated improvements in the Radio. His inventions have positively changed the broadcasting industry since nearly all modern Radio receivers make use of his three innovations. His inventions have made the functioning of Radio receivers simpler by eliminating the usage of various tuning controls.

Works Cited

Dominick, Joseph. Dynamics of Mass Communication: Media in Transition. New York: McGraw-Hill Higher Education, 2010. Print.

H2pro Company has invented wireless headphones that can work without connection through wires to electronic devices that transmit sound. These headphones will work well with smart phones and other mp3 devices that have applications of Bluetooth.

These headphones are waterproof and, therefore, can receive sound impulses even under water. These headphones will be very significant to swimmers and athletes that could be distracted by wired headphones in the course of their activity.

With their property, that makes them to apply Bluetooth, they can receive sound impulses from devices to which they are configured from as far as fifteen hundred metres in the air and up to eight hundred metres in water.

These are new inventions that will improve concentration of participants in any competition as well as keeping them updated during competition.

H2pro Company sales team are set to make sure that these headphones are made available to all people in the competition in football, swimming, and athletics. Through this device, competitors in athletic and swimming will be kept updated on the progress of events.

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The gadgets are light and, therefore, will not create discomfort to their users. On the other hand, they have voice adjustment system that will ensure that regulation of voice is made.

Sales team will carry out training on the device to ensure that team members have adequate information as they go to market the gadget. Sales team members will be taught on how to express themselves to potential customers and how to maintain good relations as customers seek to get more information about the headphones.

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Another area where the sales team will be informed is the sector on prices and different qualities of H2pro wireless headphones. In that way, they will have enough information about these headphones and their usability. Information about retail and wholesale prices will be given to these sales team members during the training.

Marketing team of H2pro Company will ensure publicity is done to ensure that these earphones are known. After extensive advertisement is made about these headphones, the marketers will be sent to major sports shops to sell these headphones.

They will also do promotion activities with a few headphones to catch the attention of athletes and swimmers and other sportsmen. These will involve attending major events that have great potential to convene many players and participants.

The headphones will be sold at slightly reduced prices during these events, which will attract players to buy. The sales team will also target major cities that have busy sporting activities that will increase the probability of creating awareness to as many people.

The sales team at H2pro will send sales representatives to major sports shops with business proposals, which will seek to open a seller-buyer relationship that would lead them to be usual buyers of the headphones.

Retail shops that will be selling H2pro wireless headphones will be subjected to offers and their prices will be reduced as according to the orders they will make.

The sales team at H2pro will acquire the schedule IAAF so that they can partner with major athletic retail shops to carry out promotion activities during the time of competition. These promotions will make the athletes from all corners of the world to be aware of these wireless headphones.

In carrying out the sales of these wireless earphones, H2pro will take into consideration the competition it will face from producers of wired headphones. Some athletes might be reluctant to purchase these new headphones because they are relatively more expensive than other headphones.

However, although wireless earphones can be used in various sports like swimming and football refereeing, H2pro Company targets athletes. This is because of their growing number and the comfort they will be at when they are using this kind of headphones than when they use other wired headphones.

In innovation of wireless headphones, however, H2pro is the first on this line. This product is made with unique qualities that will attract customers to buy.

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The sale of these headphones target athletes from around the globe. Therefore, they will offer a wide market for H2pro Company. H2pro is offering them at competitive prices although they are a little more expensive than wired headphones.

Their price is unmatchable with the efficiency and comfort its user will enjoy as they use them. On the other hand, cash flow that takes place within athletics competition is targeted by this company. What the company has not been able to achieve by now is popularity of these headphones.

However with the work done by the sales team, it is predictable that H2pro wireless headphones will not be a new thing in the mind of many athletes all over the world by the end of the first year.

H2pro Company is organized in terms of the owner of the company who is the chairman of the administrative team and the CEO.

There are departmental managers who include sales and marketing manager, who oversees marketing unit of H2pro Company; human resource manager, who is involved with acquisition of employees to the company; innovations and invention manager, who lead the innovation and creativity team, and is also the chief coordinator of any usability test in the company; and public relations manager, who represent the company in various forums in the country and outside the country, this manager is also the general manager to the company and a chief decision maker in any of the other departments.

These lie in the second rank of H2pro Company organisation. They lead project supervisors who oversee execution of plans of H2pro Company. The lowest rank in H2pro Company is the employees.

Employees are categorized into two groups i.e. permanent and those who are contracted when work increases. Of this rank, the permanent employees are ranked higher than the contractual employees.