Outbound interface as a selector?

Dan McDonald <danmcd@Eng.Sun.Com> Sun, 17 October 1999 22:33 UTC

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From: Dan McDonald <danmcd@Eng.Sun.Com>
Message-Id: <199910172118.OAA14917@kebe.Eng.Sun.COM>
Subject: Outbound interface as a selector?
To: ipsec@lists.tislabs.com
Date: Sun, 17 Oct 1999 14:18:55 -0700
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Consider the case of IPv6 link-local multicast.  Say I have two multicast SAs
for dstaddr == ff02::2 (all-routers mcast).  Let's say further that one SA is
for one link, and the other SA is for the other link.  Unless I hardcode SPIs
into the user API (which is a BAD idea), I need to distinguish between the
two SAs.  The only way I can think of is to use the outgoing interface as a
selector for outbound d-grams (and for that matter, inbound d-grams too).

Off the top of your heads, do you see anything really broken about the idea
of outbound interface as a selector?

Dan