ms6b#@ANDREW.CMU.EDU.UUCP (02/15/87)
The overall management of telephone numbers (the North American Numbering Plan - NANP) is currently being handled by Bell Communications Research, the entity jointly owned by the seven regional Bell holding companies. It worries about such things as shortages of 950 numbers, etc. Among the problems it is currently wrestling with: how will ISDN telephone numbers be assigned? For example, if AT&T starts offering ISDN service direct to large customers via the primary rate interface, what will the destination number of these customers look like? One proposal would assign a new area code (like 700) to AT&T and let AT&T hand out destination numbers to its customers. The problem with that is that the area code no longer tells you anything about the geographic location of the number. The other possibility would be to give AT&T an exchange code to use IN EACH area code. This is how it works for the non-wire line cellular telephone carriers. The problem here is that exchange codes are in short supply in some areas -- like 617, etc. -- until they get split into two area codes. By the time you hand out ISDN exchange codes to AT&T, Sprint, MCI, etc, you've used up a lot of exchange codes. This issue is being discussed in something called the NANP Forum which is coordinated by Bellcore. In general, a complete re-working of the NANP is scheduled for the 1995 time frame when telephone numbers will probably go from 7 digits to 8. Last year the French reassigned some 24 million subscriber telephone numbers to a uniform 8 digits in a massive cutover.
wales@LOCUS.UCLA.EDU.UUCP (02/20/87)
Commenting on the following message by Marvin Sirbu: In general, a complete re-working of the NANP is scheduled for the 1995 time frame when telephone numbers will probably go from 7 digits to 8. I don't understand why such a changeover (which, by the way, would be *massively* disruptive -- far more so, I dare say, than the recent French change to 8-digit phone numbers) would be necessary at all. A *far* more reasonable change (and, indeed, one I thought I had heard people on this list say was going to happen already) would be to intro- duce area codes with *any* digit as the second digit (i.e., NXX codes, as opposed to the current N0X/N1X set). This, I assume, cannot be done until 1+ dialing is in use throughout North America -- but I understood the plan was to phase in universal 1+ dialing anyway within the next few years. -- Rich Wales // UCLA Computer Science Department // +1 213-825-5683 3531 Boelter Hall // Los Angeles, California 90024-1600 // USA wales@LOCUS.UCLA.EDU ...!(ucbvax,sdcrdcf,ihnp4)!ucla-cs!wales "Sir, there is a multilegged creature crawling on your shoulder."
ms6b#@ANDREW.CMU.EDU.UUCP (02/20/87)
Rich is correct insofar as if the only issue we have to be concerned about is the growth in subscriber lines, than the switch from N0/1X to NXX would be more than adequate to carry us into the next century. Switching from N1/0X to NXX would increase the total of available numbers in the North American Numbering Plan (NANP) by a factor of 4 or 5. Whether this will in fact be enough to get us very far into the next century depends a great deal on how the available numbers are allocated, particularly in an environment of competitive carriers. If we witness a proliferation of competitive local carriers, or corporate private networks, and if each public or private carrier must be assigned exchange codes to allocate within each area code, then the rate at which exchange codes get "used up" (e.g. committed) within an area code will depend more on the rate of proliferation of carriers than on the rate of growth of subscriber lines. Granted that each such assigned exchange code would be only sparsely used, but it will be committed nonetheless. The result could well be a need to do more than switch to NXX for area codes in order to handle future growth. Alternatively, we could assign "area codes" to each competitive carrier, and let them assign exchange codes (perhaps with geographical significance like early 800 numbers). All it would take is for the Fortune 500 to each create private networks and demand their own area codes, and the supply would be quickly exhausted. It is possible that the use of CCS and database services of the type which support 800 numbers will allow the same area code or exchange codes to be used by different carriers with a database look up to determine which carrier in fact to route to. Who would run such a database? The information therein would be much too sensitive to trust to a competitor such as a BOC or AT&T.... (A similar problem occurred with the allocation of Ethernet numbers. Originally Xerox proposed to allocate numbers in blocks of 10,000 to various manufacturers. You had to use up an allocation before you could ask for more. Needless to say, IBM did not take kindly to the idea of telling Xerox, to the nearest 10,000, how many network connections it had sold! The IEEE 802 standard removes the allocation of numbers from Xerox.)