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Re: cost of residential ISDN (fwd)
- To: firstname.lastname@example.org
- Subject: Re: cost of residential ISDN (fwd)
- From: James Love <email@example.com>
- Date: Tue, 16 Jan 1996 20:43:32 -0500 (EST)
more on the issue of blockage (or nonblockage) on ISDN...
---------- Forwarded message ----------
Date: Tue, 16 Jan 96 19:08 EST
From: Marty Tennant <firstname.lastname@example.org>
To: Martin Weiss <email@example.com>
Subject: Re: cost of residential ISDN
>On Tue, 16 Jan 1996, Marty Tennant wrote:
>> Martin, I'm not sure what you mean. Could you elaborate?
>> >On Mon, 15 Jan 1996, Marty Tennant wrote:
>> >> So that means that, within a 10,000 subscriber line capacity central
>> >> 5,000 folks could be talking to 5,000 other folks on the same switch
>> >> same time. No increase in costs would result (maybe more power
>> >> and the capacity would be there from the time of installation.
>> >and congestion costs.
>Congestion costs are social costs that a user imposes on others based on
>their usage. For example, if I am a heavy user and tie up the switching
>fabric, then I can cause blockage of other users. The congestion cost is
>the cost of unrealized usage.
>Jeff Mackie-Mason and Hal Varian have written an excellent intro paper on
>this theory. It is available from their web site as well as in the IEEE
>Journal on Selected Areas in Communication (September or October 1995).
>University of Pittsburgh
Martin, this holds true in a network that has the potential for bottlenecks.
Unless contradicted by someone with direct technical knowledge, I contend
that current ISDN switches, from Nortel, AT&T or whoever, are non-blocking
switches. This does not allow for blocking within the immediate switch.
If you are speaking about interoffice trunking of ISDN calls, then there
*is* a potential for heavy users tying up the connections between the
central offices. In most large cities, there are sufficient fiber optic
connections between all CO's that this isn't a problem.
So I'm not sure your congestion costs are a real problem in the real world.