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Video broadcasting deserves special mention. Although it is terribly bandwidth-intensive and the quality is poor, it is possible to transmit packet video over the Net. Through the use of CU-SeeMe software developed at Cornell University by Tim Dorsey, and available free of charge, poor quality video is possible. Videoconferencing also is possible with a SLIP/PPP connection and a high-speed modem ([ge]14.4 Kbps). A black-and-white video camera can be had for under $100 from Connectix Corp. and others. In either case, connection is provided through a video server known as a reflector approximately 50 such sites exist. Unfortunately, video and image usage promises to bring the Net to its knees if used unwisely. Internet floodwalls are being considered to at least isolate such traffic to a segment of the Net [13-29].
Radio broadcasting makes use of packet radio systems such as RealAudio from Progressive Networks. AM radio quality is possible with a ten-second delay. As is always the case with packet-switched networks, streaming audio is subject not only to delay, but also to data loss with no opportunity for recovery. In other words, the general quality is not great, but the price is right. By way of example, the author had a number of students from Asia at a graduate-level course he taught at the University of San Francisco. Several students from Japan, in particular, regularly listened to radio broadcasts from Tokyo over the Internet. Again, the quality was not great, but because it was free the price was right. Additionally, the students really had no other means of hearing such a broadcast, or getting information from home on a timely basis. According to the Associated Press, there were over 200 radio stations broadcasting over the Net at yearend 1995. Additionally, Microsoft and NBC have plans to offer a 24-hour news channel [13-30].
Also known as IPhone, NetPhone, and Internet Voice, Internet Telephony is a means of transmitting voice over the Internet, bypassing the traditional PSTN and saving money in the process. Internet telephony is accomplished through the use of special software residing on a multimedia PC equipped with a microphone, speaker, and modem (14.4 Kbps or better). For the most part, the software works on a half-duplex basis, allowing only one person can to talk at a time using a push-to-talk protocol reminiscent of CB radio. Through appropriate modems and using recently developed software, full duplex communications also can be supported. In every case, a voice conversation currently is supported only through the use of matching software residing in both transmit/receive devices.
Whether full or half duplex, voice is not well-supported over packet networks due to issues of audio quality, packet delay, and packet loss. Additionally, it currently is necessary that both parties schedule the call in advance, typically either via e-mail over the Net or through a short preliminary telephone call. Current software/hardware technology does not allow the caller to ring the target PC over the Net. This limitation likely will be overcome in the near future through the development of a standalone device sitting between the PC and the access circuit, much like a contemporary voice/fax/modem splitter.
However, it is free if you are lucky enough to be a college student or faculty member. End users connecting to the Net directly or through an Internet Service Provider (ISP) can make use of this application essentially for free, although small usage charges may apply above a certain usage threshold. Users connecting through an information service provider (AOL, CompuServe, or Prodigy) face more significant, but still reasonable, usage charges. In any event, the cost of Internet usage compares quite favorably with long distance charges imposed by traditional PSTN carriers.
As one might expect, some of the PSTN carriers are very upset about this application. Contrary to what one might expect, others applaud it. ACTA (Americas Carriers Telecommunications Association), an association of smaller carriers, has filed a formal protest with the FCC. AT&T, on the other hand, has announced its support of Internet telephony. The carrier issue, clearly, is one of erosion of revenues. AT&Ts surprising position is a reflection of its position as the second largest ISP in the country. In fact, AT&T announced in July 1996 its intention to marry its PSTN and Internet service offerings in order to provide additional service and cost options to its customers. It would appear that AT&T intends to overwhelm its competition and dominate the Internet telephony market, which will find a constituency whether AT&T participates or not. Additionally and not surprisingly, Intel, Microsoft, and other chip and software manufacturers have thrown their weight behind Internet Telephony.
Other issues abound, including reduced tax revenues at the local, state, and federal levels. The Universal Service Fund will be threatened unless ISPs and backbone carriers are required to contributethe upshot will be an increased burden on PSTN users in support of local service cross-subsidies to maintain a high level of network access to rural areas at reasonable cost to those end users. ISPs face increased costs for servers, modems, local loops, and links to the backbone networks in support of increased traffic. The backbone networks, that are already experiencing brownout and which are facing meltdown, will experience extra pressure on scarce and expensive bandwidth, which will force additional investmentand on, and on, and on.
Realizing that we cant solve this dilemma within the covers of this book, perhaps it is time to mention a few of the providers of such software (and the specific products). Those vendors include Electric Magic (NetPhone), FreeTel Communications (FreeTel), Netscape Communications (CoolTalk), NetSpeak (WebPhone), Quarterdeck (WebTalk), Third Planet Publishing (DigiPhone), and VocalTec (Internet Phone). Motorola and a large number of other manufacturers are now packaging Internet Phone capabilities into their new modems; these powerful modems contain Digital Signal Processors (DSPs) which are capable of accommodating the necessary compression algorithms. Internet telephony, as you may have sensed by this point, is a very hot topic at the time of this writing. As an indication of that fact, note the sheer number of references from which this treatment gathers information [13-8] and [13-31] through [13-48].
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