Re: [homenet] dst/src routing drafts (for IETF-91 rtgwg)

Tim Chown <> Tue, 28 October 2014 19:46 UTC

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From: Tim Chown <>
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Date: Tue, 28 Oct 2014 19:44:45 +0000
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To: "Fred Baker (fred)" <>
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Cc: "" <>, Mikael Abrahamsson <>, "" <>, David Lamparter <>
Subject: Re: [homenet] dst/src routing drafts (for IETF-91 rtgwg)
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On 22 Oct 2014, at 21:16, Fred Baker (fred) <> wrote:

> On Oct 22, 2014, at 12:06 PM, David Lamparter <> wrote:
>> On Mon, Oct 20, 2014 at 10:40:33PM +0200, David Lamparter wrote:
> Speaking strictly for myself, I’m not sure why homenet is relevant. The technology is related to networks that have different routing depend on on one’s use case. A class of solutions for it has been called the “fish” problem, and built using multi-topology routing. In homenet, it’s called SADR, and is primarily about egress routing (routing to an egress to an upstream ISP that gave you a PA prefix). While one doesn’t really want to confuse theory with practice, in theory it could be used between points of a network, to prevent folks using one set of prefixes to talk with another set, or to force routing of some sessions in some ways.
> Personally, those are a class of problems I associate with campus networks more than residential networks.

I suspect most campus networks will have a single /48 from their NREN, or a /48 PI. I’m not aware of any campuses in the UK which are multi-homed with dual /48, though I understand some Internet2 campuses may be. 

(As an aside we’ve just run out of our v4 /16…)

Homenet has ‘designed in’ future multihoming, which is rare today. In the homenet case the multihoming may presumably be more commonly for different services to the home?