Path: utzoo!mnetor!uunet!husc6!mailrus!ames!pasteur!ucbvax!UM.CC.UMICH.EDU!Doug_Nelson From: Doug_Nelson@UM.CC.UMICH.EDU Newsgroups: comp.protocols.tcp-ip Subject: Re: Subnetting Message-ID: <3026964@um.cc.umich.edu> Date: 7 May 88 15:11:58 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 26 In message <1607@erix.UUCP>, Per Hedeland writes: > a) It appears that the intended use of subnetting assumes that all the "subs" > of a "whole" net are interconnected, i.e. the backbone and the client > segments in our case should be "subs" of the same "whole" - in particular, > "automatic" routing by means of routed (which we desire) will not work > otherwise, as far as I can understand. Yes, that has to be true - you can only advertise your full network, not your subnets, to the Internet at large. > b) "Subs" of a given "whole" must be of equal size. This is a mistaken assumption. There is nothing that prevents you from using subnets of different sizes on a given net, except for software that isn't up to speed on subnetting (notably SunOS 3.x). For example, our campus-wide network is a class B sized subnet of a class A network. The Merit network itself is a class A/2 subnet, and Univ of Michigan has parceled out a number of class C-sized subnets. I plan to pass out class C-sized subnets of our network (or possibly smaller) to several other campus Ethernets, as soon as we get SunOS 4.0 installed. Doug Nelson den@serv1.cl.msu.edu Michigan State University 08071den@msu.bitnet Computer Laboratory