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III. Wireless standards
This page discusses standards, uniform rules cellular systems follow. Learning standards teaches how cellular radio is organized. Unless a company foregoes the standards process, such as Motorola with their iDEN system, a radio technology will always have a single industry name and a standard to go with it. Learning about standards and the industry names that go with them, clears up much confusion.
A standard is an accepted or established rule or model. They are a set of agreed on principles and practices. Different industry standards specify everything from film roll speed to electrical outlet shapes. Most standards are voluntary but everything works better if manufacturers agree on them. Who wants a dozen credit card sizes? Rather than specifying the construction, size, or shape of cellular equipment, cellular standards more often mandate a process, they dictate how a system works. Many rule making groups produce standards.
TIA (external link) means the Telecommunication Industry Association, a group accredited by the larger American National Standards Institute or ANSI (external link). The TIA, along with the T1P1 Committee of the Alliance for Telecommunications Industry Solutions or ATIS , develop North American wireless standards. The IS means an interim standard, one still developing. The TR-45 committee within the TIA coordinates each standard's work, assigning sub-committees to specific projects. (Click here (external link) for a great overview of their work.) Lastly, spread spectrum or CDMA based PCS relies on TIA-IS- 95 as well as an ANSI standard: ANSI J-STD-00 (external link). The European Telecommunications Standards Institute or ETSI (external link) develops European standards. Like those for GSM.
Cellular standards set rules that mobiles, base stations, mobile switches, cellular databases, and other network elements follow to communicate with each other. Since wireless has many operating systems it has many standards. Some cover small details and others broad areas. North American cellular standards strive to make every mobile and every cell site across the hemisphere work together.
Network standards like TIA IS-41 specify how individual cellular systems communicate over the public switched telephone network or PSTN with every like cellular system and its associated resources. IS-41 provides a common operating framework for different technologies. Its full and telling name is "Cellular Radio telecommunications Inter-System Operations." IS-41 provides the connections to network resources that an AMPS, TDMA, or CDMA systems needs to work. So, IS-41 is not technology dependent, rather, all cellular systems, no matter what type, use the IS-41 protocol to permit calling.
As David Crowe puts it, "Automatic roaming with a cellular phone is made possible by the TIA/EIA-41 standard that provides intersystem handoff, call delivery, remote feature control, short message delivery, validation and authentication through an inter-system messaging protocol." [CNP (external link)] IS-41 makes everything go. Let's move now from a networking standard to a specific technology standard.
Radio or "air interface" standards like TIA IS-54, now rolled into IS-136, specify a technology's operating details. IS-136 is the time division multiple access or TDMA based cellular scheme we looked at briefly in the history section. It's what AT&T uses for their national cellular network; many local carriers use it as well. The IS-136 standard details frequencies, data formats, signalling requirements and other steps used to make a call. What we Americans call "the nitty gritty."
Global Engineering (external link) sells most wireless standards. The documents are expensive and obtuse, with little information relevant to the average telecom enthusiast. Unless you work in a field directly impacted by a standard I would not recommend buying them. Consult books, newsletters, and magazines instead that analyze the standards for you. Check out the files below, then read the informative comments from a telecomwriting.com reader who has actually worked on standards. You won't find such background on many other sites . .
For more on the cellular radio standards, check out this section from Understanding Digital PCS: The TDMA Standard, by Cameron Kelly Coursey (11 pages, 63K in .pdf)
More information on this title is here (external link to Amazon.com)
Need a quick overview of the different electronic associations? Click here for information from Travis Russell's Telecommunications Protocols, 2nd Edition (6 pages, 194K)
More information on this title is here (external link to Amazon.com)
More Discussion
Thanks to Bill Price for the insights below, he graciously took the time to send them in. He relates:
"Sales of standards documents fund the bureaucratic empires of the standardizing organizations, but do not fund any research or development activities."
"From 1978 through 1983 or 1984, I was heavily involved in standards-development efforts in IEEE, ANSI, and ISO arenas. In particular, I was an individual contributor at the Technical Subcommittee level (IEEE, ANSI) and Expert/Working Group (ISO), a company representative
at the Technical Committee level (ANSI), a Member Body Delegate at the ISO Technical Subcommittee level, and a Member Body Delegation Technical Advisor at the ISO Technical Committee level. Now, what does all that mean?"
"It may all sound grand and glorious, but being a US delegate to an ISO committee is no big deal. Anybody can do it. All you need is somebody to pay the bills--and it won't be the sales of any standard you might help to develop. In fact, your company not only gets to pay your expenses, but they also pay the standards-development organization for the license for them to participate. The license is usually called a Membership or Service fee, in the range of $50-$500 per year. This is supposed to cover office expenses of the Sponsoring Organization, which is usually a trade group."
"The formal requirement for membership in any standards group is 'willing and able to participate in the work.' The real meaning of this is that you've got to know something about the subject matter, and you have to have someone to pay your expenses to the meetings. Of all the people I worked with, about 200 in all, in this standards stuff, there was only one who was not paid for by a company or agency that either produced or consumed the stuff of the standard. That one was partially funded by a grant from the NBS (now NIST); the rest came from his own pocket."
"Organizations" can be producers and consumers: the companies that make the affected products, and companies or government agencies and the like that buy the affected products. On some standards, like those related to safety, some members are recruited (if necessary) to represent "the public interest," whatever that is. ANSI rules for accreditation expect a more-or-less balanced membership, but that's sometimes hard to get. On the other hand, IEEE rules are incredibly loose. Most ANSI-accredited committees have quarterly meetings, rotating around the country, to encourage participation by geography. Most IEEE committees that I've been involved with, for example, meet the third Thursday of each month at Ricky's Hyatt House in Palo Alto, California.
"A supplier participates so that its products will be acceptable in the market upon adoption of the standard. The company sends a representative (or more than one), chosen to best represent the company's interests in the personal/technical/corporate/international politics of the subject, as the company sees best. Because the company's interests have already influenced the hiring and job-assignment decisions, the people they send will already be in agreement with the company's goals."
"As to profiting by standards writing, there was a standard that IEEE wanted to develop because they saw it as a popular subject -- they were quite up-front in admitting that they lusted for the publication rights to the standard. A more mainstream group also wanted to develop the standard, and formed their committee first. The IEEE raised a fuss with ANSI, and as a final result the committees merged and IEEE got the publication rights. I was one of the participants in that fiasco: the merger worked because there was an almost complete overlap in membership between the IEEE committee and the mainstream committee."
"The benefits to participation in standards work are usually listed as a) influence over the content of the standard, and b) early knowledge of the content of the approved standard, before approval. The real meaning of the second point is that you, as a participant, already have all the information that will be in the expensive document. You will, of course, share this information within your company -- before committee action -- to get consensus from your coworkers and your management. Your company will start benefiting from the content of the standard before its publication, so it really doesn't need to buy anything from IEEE or from Global Engineering."
"It's not the participants that pay for the documents -- it's all of us poor slobs who didn't have the time, money, or timely interest to get into the development of the standard. Let me say in closing that the publication income consideration is not universal. For example, the American Plywood Association sponsors ANSI standards in its area of interest. APA publishes these standards on the web, freely available to anyone who can find their website."
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