Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!rutgers!mit-eddie!uw-beaver!ubc-cs!eric!zaphod.mpr.ca!parker
From: parker@zaphod.mpr.ca (Ross Parker)
Newsgroups: comp.protocols.tcp-ip
Subject: Changing subnet masks
Message-ID: <1855@eric.mpr.ca>
Date: 31 Oct 89 01:24:43 GMT
References: <2781@jhunix.HCF.JHU.EDU>
Sender: news@eric.mpr.ca
Reply-To: parker@zaphod.mpr.ca (Ross Parker)
Organization: Microtel Pacific Research Ltd.
Lines: 31

Up here in BC we have a network known as BCNet which connects our three
universities and a number of research institutions. The current network
is set up with a backbone on network 128.189, and satellite networks
using network number 134.87. The satellite networks have all been assigned
chunks of the third byte to be used at their whim... i.e. here at MPR, we
are free to use any number between 134.87.131.xxx and 134.87.140.xxx (where
'xxx' is of course between 1 and 254). The subnet mask is currently set to
0xffffff00. As some of our satellite networks have few hosts, we want to
change the subnet masks to, say, 0xffffff70, leaving 5 bits, or 32 possible
host addresses per subnet.

The 'satellite' networks are hung off of the main network using either
Proteon P-4200 routers, or Sun 3s acting as routers. These routing
boxes all know which satellite networks contain which chunks of the
'134.87' address space.

The $64,000 question is: do we need to change all subnet masks at the
same time (which would be a *real* drag...), or can multiple subnet
masks exist on the same network at the same time?

Any comments, help, suggestions, money :-) would be greatly appreciated.



Ross Parker      				| Why do they put me down?
Microtel Pacific Research Ltd.			| Make out that I'm a clown?
Burnaby, B.C.,	     				| I drink scotch whisky all
Canada, eh?	     uunet!ubc-cs!mpre!parker	|	 day long
(604)293-5495	     parker@mpre.mpr.ca		| Yeah I'm gonna save my money
Disclaimer:					| (gonna put it all away...)
My fingers are doing all the work...		| 'Cause I'm a Scotsman