by Abhijit S. Pandya; Ercan Sen CRC Press, CRC Press LLC
ISBN: 0849331390 Pub Date: 110198
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V. Telecommuting
Crowded and inadequate urban infrastructures such as roads are making working in downtown business districts almost impossible. Due to congested roads during busy hours, commuting between work and
home is becoming a nightmare. Workers have to spend a considerable amount of their time i.e., 1 to 3 hours each day for commuting.
Figure 3-8 Video conferencing.
Most recently, due to advances in telecommunication, telecommuting has become an alternative to traveling each day between work and home through congested roads. Both government agencies
federal, state and local and businesses are promoting telecommuting as a solution to reduce commuting to crowded urban areas. Recent experimentation with telecommuting is indicating significant
improvements in workers’ productivity and morale.
As with the other telecommunication services we described in this chapter previously, telecommuting also depends on high bandwidth and low bandwidth cost. Telecommuting will require combinations of
video telephony and video conferencing, and ubiquitous access to computing resources of a company. In other words, terms of access to company resources and interaction with clients or co-workers have to be
made transparent between physically being at a company’s premise or telecommuting from home or a satellite location. ATM technology will certainly make telecommuting affordable to many organizations
and improve the traffic conditions of the urban areas.
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Copyr ight © CRC Pr ess LLC
by Abhijit S. Pandya; Ercan Sen CRC Press, CRC Press LLC
ISBN: 0849331390 Pub Date: 110198
Previous Table of Contents Next
Chapter 4 Integration of Various Access Node Technologies into ATM
Networks
Another key promise of ATM technology is to provide a platform to integrate today’s various access node technologies such as wireless, Plain Old Telephony POT, Data, Cable-TV. Hence it offers an affordable and
easy access among the networks based on these diverse access technologies. Similarly, ATM is also capable of providing access among different transport technologies such as SONETSDH and Frame Relay. Each of these
access and transport technologies we have just mentioned were developed to address particular needs and were performed efficiently in their targeted communication domain. However, due to globalization of communication
and the need for offering combined services such as voice, video and data, the networks built on these access and transport technologies had to be interconnected. ATM technology is well suited for this enormous
interconnectivity task. In this chapter, we will elaborate on how ATM technology can be applied in each of these areas to provide interconnectivity.
I. Wireless Networks
In recent years, wireless technology provided one of the fast growth areas for the communication industry worldwide. The key drivers for this tremendous growth in the wireless segment were:
• The promise of providing communication capability anywhere, any time, even while on the move. • Rapid infrastructure build up at an affordable cost.
While tremendous growth in the U.S. can be mainly attributed to the first driver, in other industrialized countries and developing countries the second driver has been more dominant than the first one. For example, in most of
these industrialized countries, the government has generally owned the traditional PSTN networks. Due to this monopolistic structure, the telephone service rates have been rather-high compared to the U.S. However, due to
the second driver, in some of these countries where the competition is allowed, private companies were able to build wireless networks to compete with the government owned traditional telephone service. In fact, Internet
access in these countries is still not affordable by the majority of the population. This is mainly due to dependence of Internet access on the traditional telephone access via modem connection. On the other hand, in the developing
countries such as China where the problem is the lack of PSTN infrastructure, the wireless technology offers an attractive solution for rapid communication infrastructure build up.
Although the current wireless technology offers mobility and rapid and affordable communication infrastructure
One of the most recent developments in the communication area is the packetized voice transport over data networks and the Internet using protocols such as voice over IP VOI or voice telephony over ATM VTOA.
The packetized voice allows suppression of silence periods of natural speech, hence reducing the bandwidth requirement as well as allowing sharing of the same physical channel by multiple voice connections, i.e.,
statistical multiplexing.
In traditional wireless networks, digitized voice samples in Pulse Code Modulation PCM format are carried over 64 Kbps DS0 channels. However, by use of ATM technology in wireless networks as shown in Figure 4-1, the
packetized voice can be transported more efficiently from base stations to a central office location. At the central office, the voice can be converted to DS0 format to be carried over traditional PSTN networks or the packetized
voice can be carried over Public Data Networks PDN such as Frame Relay, ATM and the Internet networks. Carrying voice over PDNs offers a more cost-effective alternative. Additionally, more voice calls can be carried
out on the same physical link between base stations and central office. Advantages of using ATM between base stations and central office is twofold:
• Higher concentration on the physical links between base stations and central office, • Interoperability with PDNs to allow cost-effective voice transport alternatives.
The interoperability feature of ATM technology with PSTN and other data networks will be further discussed in Section 4.2 and Section 4.3, respectively.
