Re: Possible ambiguity of Hop-by-Hop Options header processing text in draft-ietf-6man-rfc2460bis-08

Joe Touch <touch@isi.edu> Mon, 20 February 2017 16:48 UTC

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Subject: Re: Possible ambiguity of Hop-by-Hop Options header processing text in draft-ietf-6man-rfc2460bis-08
To: "C. M. Heard" <heard@pobox.com>, IETF <ietf@ietf.org>, 6man WG <ipv6@ietf.org>
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From: Joe Touch <touch@isi.edu>
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Date: Mon, 20 Feb 2017 08:48:19 -0800
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On 2/19/2017 3:14 PM, C. M. Heard wrote:
> ...
> On that basis I would like to suggest changing the note as follows:
>
>    NOTE: While [RFC2460] required that all nodes must examine and
>    process the Hop-by-Hop Options header, it is now expected that nodes
>    along a packet's delivery path, other than the source and destination
>    nodes, will examine and process the Hop-by-Hop Options header only if
>    explicitly configured to do so.
>
It would be useful to be more clear about destination - e.g., as
indicated up the destination IP address.

I.e., AFAICT an intermediate stop of a "loose source route" (using the
routing header) should be able to alter the HBH headers at will.

Joe