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From: jal@acc (John Lauro)
Newsgroups: comp.sys.apollo
Subject: Re: subnets, proxy ARP
Message-ID: <1990Jul31.132558.7841@caen.engin.umich.edu>
Date: 31 Jul 90 13:25:58 GMT
References: <12081@sdcc6.ucsd.edu> <1990Jul30.210655.19558@terminator.cc.umich.edu>
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Organization: University of Michigan - Flint
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In article <1990Jul30.210655.19558@terminator.cc.umich.edu> rees@citi.umich.edu (Jim Rees) writes:
>In article <12081@sdcc6.ucsd.edu>, mikulska@odin.ucsd.edu (Margaret
>Mikulska) writes:
>  Does Apollo support proxy ARP ? (We are currently running SR10.2).
>
>Proxy ARP is a Bad Thing.  I certainly hope Apollo doesn't support it.
>
>I thought everyone had subnets now.  Do you have some machine that doesn't?
>Or do you need proxy ARP for some other reason?

Don't know about Jim, but we have subnets and use proxy ARP.

When we had an Apollo acting as a router, we ran into problems because
it didn't support proxy ARP.  If your gateway to the internet doesn't
support RIP, it makes it hard for computers on the other side of the router
to access anything outside of your domain...  We finally ended up getting a
dedicated Proteon router.  In our situation proxy ARP where we only need
to set up the subnets for the routers and have proxy ARP enabled is easier
to maintain then RIP.  (Not to mention keeps all those RIP broadcasts off
the net.)  We will be upgrading our connection to the internet, but until
then, we have to use proxy ARP...  Proxy ARP may not be the best solution,
but it appears to be better than what Apollo supports (RIP).

I admit, I am not very knowledgeable in this area, so enlighten me... :-)
The only advantage I see of RIP over proxy ARP is if there are multiple
paths the data could take if a link goes down, etc...  If no redundant
paths, what's the "Bad Thing" about proxy ARP?  If you change a subnet
or something, all you do is change it on the router that effects a
subnet, so maintenane is easy and quick.  As easy if not easier than RIP.

Or does Apollo support something better than RIP?  I noticed they supply
source to gated which includes RIP, EGP, and HELLO.  However, I didn't look
into it, and know next to nothing about EGP and HELLO.

   - John_Lauro@ub.cc.umich.edu