Single subnet
Dave Katz <katz@merit.edu> Fri, 18 May 1990 15:34 UTC
Received: from merit.edu by NRI.NRI.Reston.VA.US id aa09213; 18 May 90 11:34 EDT
Received: Fri, 18 May 90 10:33:12 EST by merit.edu (5.59/1.6)
Date: Fri, 18 May 1990 10:33:12 -0500
From: Dave Katz <katz@merit.edu>
Message-Id: <9005181533.AA04837@merit.edu>
To: fddi@merit.edu
Subject: Single subnet
Status: O
I'm working on an article for SIGCOMM CCR on running IP and CLNP over FDDI and came upon an interesting question: Is there any reasonable way of having single-MAC stations on both rings when using the single-subnet approach? The problem comes when a station on each ring needs to talk to a station on the other ring (and both are single-MAC). The initiator has no knowledge of where the destination is, but knows it's on the same subnet, and sends an ARP. The real destination cannot respond (since it won't hear the ARP), so the only logical choice is a dual-MAC router. However, that router will not have a priori knowledge of where the destination is either, so it cannot blindly answer the ARP. I suppose that the router could ARP out both rings for the destination and if it finds it on the other ring could then send an ARP reply (but the timing on this could be tricky). Ambiguities due to the network wrapping could presumably be eliminated by using a "different" ARP on each ring (and each single-MAC station would ignore the other's ARP in this case). Comments? By the way, CLNP does not suffer from this problem, since routers know a priori where all the hosts are.
- Single subnet Dave Katz
- Re: Single subnet Steve Deering
- Re: Single subnet Dave Katz
- Re: Single subnet Steve Deering
- Re: Single subnet Vernon Schryver
- Re: Single subnet Steve Deering
- Re: Single subnet Dave Katz
- Re: Single subnet Vernon Schryver
- Re: Single subnet Steve Deering
- Re: Single subnet Dave Katz
- Re: Single subnet Dave Katz