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From: ketell@mercury (Gregory Ketell)
Newsgroups: comp.unix.wizards
Subject: laptop internet addresses
Message-ID: <27035@adm.brl.mil>
Date: 28 May 91 21:32:04 GMT
Sender: news@adm.brl.mil
Lines: 32

> Date: 	Tue, 28 May 91 14:16:40 EDT
> From: "Peter J. Welcher (math FACULTY" <pjw@usna.navy.mil>, jw@math30,
>         ")"@BRL.MIL

> Laptop PC's and Unix boxes will be upon all us administrators soon.
> Complete with Ethernet interfaces. My question: how do you assign
> Internet addresses to people who may plug into different subnets on
> different days ? If you give them multiple addresses you could eat up
> a lot of address space in a hurry ?

> This is going to become a potential hassle in the next year or two. 
> How are people going to deal with it ?

I may catch a lot of flak from the Gurus but here is my view:

Why bother giving them multiple addresses at all.  Give each machine a 
single address, whatever network they hook up to they will still be 
reachable.  (ex.  You can reach me, I can reach you but we are not only
on different subnetworks but across the nation.).  

Just assign each machine the IP address for their "Home Connection", ie
if they are in your math subnetwork just assign them an address on that 
subnet.  When they hook up to another net they will operate on that net
with their own address.  

Admittedly this will only work as long as both subnets can reach each other.

Greg Ketell
Networks Administrator
Computing Services
Cal. State Univ., Hayward
ketell@pyr.csuhayward.edu