Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!rutgers!ames!ucbcad!ucbvax!ANDREW.CMU.EDU!ms6b# From: ms6b#@ANDREW.CMU.EDU.UUCP Newsgroups: mod.telecom Subject: Re: North American Numbering Plan (8-digit numbers??) Message-ID: Date: Fri, 20-Feb-87 14:26:35 EST Article-I.D.: andrew.oUD-rgy00UgcyxI0T1 Posted: Fri Feb 20 14:26:35 1987 Date-Received: Mon, 23-Feb-87 02:55:13 EST References: <870220.181153z.01473.wales@DIANA.LOCUS.UCLA.EDU> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 34 Approved: telecom@xx.lcs.mit.edu 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.)