Re: [v6ops] I-D Action: draft-ietf-v6ops-design-choices-04.txt

Brian E Carpenter <brian.e.carpenter@gmail.com> Wed, 18 February 2015 22:51 UTC

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Date: Thu, 19 Feb 2015 11:51:23 +1300
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
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Subject: Re: [v6ops] I-D Action: draft-ietf-v6ops-design-choices-04.txt
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>  It is very difficult to impossible to ping a link-local address
>  from a device that is not on the same subnet. This is a	
>  troubleshooting disadvantage, though it can also be viewed as a
>  security advantage.

I am puzzled by how it could ever be possible at all.
Link-local addresses are by definition meaningless off
the link in question, and they should never even be known by
any node on another link. (And of course it gets even more
complicated on devices with several interfaces, such as routers,
since a link local address is only meaningful with a ZoneID,
and that is a node-specific value, meaningless to other nodes
on the *same* link.)

   Brian