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The 3G/IMT-2000 initiative is an attempt by standards committees to define the future of cellular/PCS radio interfaces. It is doomed to failure, like many other premature standardization efforts that litter the byways of history. Ironically, international standardization is needed, but for network protocols and not for radio interfaces.
Computer programming languages have been around much longer than cellular systems, and standardization (whether formal or de facto) has been a mixed blessing. Many languages, such as academia’s Algol-68, IBM’s PL/1 and the U.S. military’s ADA, have come with imposing specifications developed by a committee or by a large company, but all eventually fell by the wayside (if you have never heard of these programming languages, then my point is proven). The most important programming language of the 1990s is C (and its derivatives C++ and Java), developed by a couple of smart guys at Bell Labs. The specification was published in a thin book (of which the actual specification occupied only a handful of pages) and the language was not standardized until it had first become a significant programming language in academia and then in business and engineering. Standardization of this language in the mid-1980s was important, both to resolve some deficiencies and ambiguities in the language specification in a single way, and to standardize the library of functions that supports it. It was important that standardization occurred, but also important that it did not occur too early.
Radio interfaces are still evolving too rapidly to be standardized. The question of whether CDMA is better than TDMA cannot yet be answered. Nor even the more fundamental question of whether digital is always superior to analog. Will it be Beta versus VHS (victory of the inferior), C versus Pascal (victory of the superior) or AM versus FM (peaceful co-existence)? Standards committees (especially at the international level) have to operate by consensus, and there can be no consensus until all technologies have had a chance to be proven in the marketplace, and a decade to evolve to fulfil their potential. Only then can the fundamental limitations of the technology be understood, along with the consumer needs that remain unaddressed and that truly require a next generation system. The worst possible outcome would be if the ITU was able to cajole and bully companies into marching single file, resulting in a compromise system that would probably be a major market failure.
The major error of the ITU is their emphasis on high-speed data. Wireless data has always been tomorrow’s technology, probably because of the emphasis on high-speed, real-time consumer applications, at the expense of more mundane low-speed, non-realtime commercial applications, a tendency that the ITU has taken to a utopian extreme. High-speed wireless data is certainly technically feasible; it is simply not economic due to the disparity between the bandwidth required for voice (8 -13 kbps) and that required for high-speed data (64kbps - 2Mbps).
Another emphasis of the ITU is on defining a long list of exotic features that the vast majority of subscribers will never use. These features are largely used by one camp (GSM versus D-AMPS versus CDMA) to attack the capabilities of the others. Those with the longest list of under-utilized features win, according to some. This is as productive as building a wall around your house because you cannot get along with your neighbors.
More emphasis needs to be placed on integrating the world’s two mobile application network protocols: GSM MAP and TIA/EIA-41 (formerly known as IS-41). There is no reason that phones could not seamlessly operate on different frequency bands using a variety of radio interfaces if better integration between these two protocols was available. Currently, GSM and TIA/EIA-41 differ in many ways, including feature control, short message delivery, mobile handoff and authentication. Moving from one backbone network to another means that most services, beyond the ability to make and receive calls, are lost. It is possible that integration of these two protocols will never really be feasible, but producing a second generation network protocol that incorporates the best of GSM and TIA/EIA-41, and that provides backwards compatibility ... that would be an achievable goal (perhaps such a protocol could be called Inter-MAP, in honor of the success of the Internet in joining together disparate LAN protocols through a common intermediary or, more whimsically, iMAP, with the spec provided in translucent teal binders). Existing air interfaces could be adapted to this new network protocol with modest modifications.
Using authentication for an example, the TIA is already developing a second generation of authentication algorithms. Why not use this as an opportunity to develop algorithms that would be applicable to use in a GSM Smart Card as well?
Feature control is another example. GSM provides special air interface messages to control each feature (e.g. call forward unconditional), making it slow to adopt new features. TIA/EIA-41 uses * feature code strings (e.g. *73 often disables call forwarding), which is more adaptable, but less efficient in the use of radio resources (because a voice channel has to be allocated). Inter-MAP could allow both methods to co-exist, with the phone using the GSM method when it is available for a particular feature, and the TIA/EIA-41 method at other times, or when a feature requires use of a voice channel (e.g. Cancel Call Waiting, which is a feature that operates only for a single call).
Another big weakness of wireless telecommunications systems is their reliance on SS7 message transport services. While this protocol is very robust, and works well for national networks, it is very awkward to use for international networking. Furthermore, there is little integration between the wireless users of SS7 (GSM MAP and IS-41) and wireline (ISUP). Seamless international wireless/wireline signaling could allow least-cost routing of calls from a wireline phone in one country to an international roamer across the street in the same country, a call that currently requires two international long distance legs. However, the canyon between wireless and wireline currently appears to be even wider and deeper than between cdma2000 and W-CDMA proponents.
If we consider a decade the time required for a major new technology to mature, then network standards are ready for a new initiative of standardization (IS-41 was first published in 1987). The development of digital radio interface standards is much more recent, and they need several more years of breeding before the weakest can be culled from the herd. The ITU is certainly earnest and well-meaning, but the fact that next year ends with 3 zeroes does not mean that it is an especially auspicious year for standardization. Sure, a new acronym will be required (IMT-2004 just will not do) but that is a small price to pay.
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