Re: Fwd: New Version Notification for draft-hinden-6man-hbh-processing-01.txt

[Nick Hilliard <[e-mail]>]

Hi Bob, Gorry,

Couple of things on this.

- draft-hinden-6man-hbh-processing is not the document to have 
terminology statements about control / forwarding plane / fast path / 
slow path / etc.  The topic is more subtle and nuanced than can be dealt 
with in a summary of a draft which addresses a different topic.  The 
ietf really needs a proper document to discuss the issue because the 
terms are used in quite a lot of discussions relating to packet 
forwarding, and several subtleties are germane to this draft.

- Is it correct to conclude that this doc changes the semantics of HBH 
from only being processed when "explicitly configured to do so" to "MUST 
process"?  The text in the draft is ambiguous in the sense that it could 
mean:

1. nodes MUST examine at least one HBH EH and MUST process the first 
Option in the fast path, or
2. if a node is configured to process HBH EHs, it MUST process the first 
Option in the fast path.

- signaling slow path HBH processing via the Router Alert option should 
be interpreted in the context that if a HBH packet reaches the slow 
path, this should be treated as something of a curiosity, i.e. the 
exception rather than the rule.

- consequently + for other reasons, it might be an idea to update the 
text in the security considerations from "Due to this it's common for 
transit routers" to "Due to this, it is routine for transit routers"

- given the many and increasing orders of magnitude of difference 
between fast path and slow path processing speed, I really question the 
wisdom of making any declarations at all about slow path processing. 
This is writing cheques on an empty account.  We need to deprecate this 
idea completely - it's been entirely non-viable for many years.

- nit: all instances of "it's" except for the last one in section 8 
should be changed to "its"

Nick

Bob Hinden wrote on 02/06/2021 19:31:
> Hi,
> 
> We posted a new version of draft-hinden-6man-hbh-processing.    The 
> changes include:
> 
>     *  Expanded terminology section to include Forwarding Plane and
>        Control Plane.
>     *  Changed draft that only one HBH Option MUST be processed and
>        additional HBH Options MAY be processed based on local
>        configuration.
>     *  Clarified that all HBH options (with one exception) must be
>        processed on the Fast Path.
>     *  Kept the Router Alert options as the single exception for Slow
>        Path processing.
>     *  Rewrote and expanded section on New Hop-by-Hop Options.
>     *  Removed requirement for HBH Option size and alignment.
>     *  Removed sections evaluating currently defined HBH Options.
>     *  Added content to the Security Considerations section.
>     *  Added people to the acknowledgements section.
>     *  Numerous editorial changes
> 
> We think this resolves most of the issues raised on the list and at the 
> pervious IETF meeting.
> 
> Please review and comment on the list.
> 
> Bob & Gorry
> 
>> Begin forwarded message:
>>
>> *From: *[e-mail] <mailto:[e-mail]>
>> *Subject: **New Version Notification for 
>> draft-hinden-6man-hbh-processing-01.txt*
>> *Date: *June 2, 2021 at 11:27:07 AM PDT
>> *To: *"Robert M. Hinden" <[e-mail] 
>> <mailto:[e-mail]>>, "Godred Fairhurst" 
>> <[e-mail] <mailto:[e-mail]>>, "Gorry 
>> Fairhurst" <[e-mail] <mailto:[e-mail]>>, 
>> "Robert Hinden" <[e-mail] <mailto:[e-mail]>>
>>
>>
>> A new version of I-D, draft-hinden-6man-hbh-processing-01.txt
>> has been successfully submitted by Robert M. Hinden and posted to the
>> IETF repository.
>>
>> Name:draft-hinden-6man-hbh-processing
>> Revision:01
>> Title:IPv6 Hop-by-Hop Options Processing Procedures
>> Document date:2021-06-02
>> Group:Individual Submission
>> Pages:13
>> URL: 
>> https://www.ietf.org/archive/id/draft-hinden-6man-hbh-processing-01.txt
>> Status: https://datatracker.ietf.org/doc/draft-hinden-6man-hbh-processing/
>> Html: 
>> https://www.ietf.org/archive/id/draft-hinden-6man-hbh-processing-01.html
>> Htmlized: 
>> https://datatracker.ietf.org/doc/html/draft-hinden-6man-hbh-processing
>> Diff: 
>> https://www.ietf.org/rfcdiff?url2=draft-hinden-6man-hbh-processing-01
>>
>> Abstract:
>>   This document specifies procedures for how IPv6 Hop-by-Hop options
>>   are processed.  It modifies the procedures specified in the IPv6
>>   Protocol Specification (RFC8200) to make processing of IPv6 Hop-by-
>>   Hop options practical with the goal of making IPv6 Hop-by-Hop options
>>   useful to deploy and use in the Internet.  When published, this
>>   document updates RFC8200.
>>
>>
>>
>>
>> The IETF Secretariat
>>
>>
> 
> 
> 
> --------------------------------------------------------------------
> IETF IPv6 working group mailing list
> [e-mail]
> Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
> --------------------------------------------------------------------
>