Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!ncar!boulder!daemon
From: RAF@CU.NIH.GOV (Roger Fajman)
Newsgroups: comp.dcom.sys.cisco
Subject: Re:  Serial interfaces IP number question
Message-ID: <24957@boulder.Colorado.EDU>
Date: 21 Aug 90 04:23:32 GMT
Sender: daemon@boulder.Colorado.EDU
Lines: 12

> Well, I really like the idea I heard someone suggest a while ago on some
> other list - assign the subnet bits high-bit first, and the host addresses
> low bits first.  This allows you to easilly expand the subnet field as
> the number of nets you are actually using goes up.

We did that, but it didn't work out very well in practice.  The problem
is that the subnet mask exists in so many places (routers and hosts)
that people get very upset when you want to change it.  So we finally
settled on a 7 bit subnet mask and got a second class B address to use
when we run out of subnets.  That probably will be next year sometime.
We will have to assign a subnet address from each net number to our
backbone networks in order to keep the subnets of each net contiguous.