Re: <draft-ietf-6man-rfc1981bis-05.txt>

[Bob Hinden <[e-mail]>]

Mike,

> On Apr 3, 2017, at 10:24 AM, C. M. Heard <[e-mail]> wrote:
> 
> Greetings,
> 
> 1.) In Section 5.3, the fourth paragraph up from the bottom of Page 9
> would, in my opinion, be clearer with the following change:
> 
> OLD:
>   The node then uses the value in the MTU field in the Packet Too Big
>   message as a tentative PMTU value or the minimum IPv6 next hope MTU
>   if that is larger, and compares the tentative PMTU to the existing
>   PMTU.
> 
> NEW:
>   The node then uses the value in the MTU field in the Packet Too Big
>   message as a tentative PMTU value or the IPv6 minimum link MTU
>   if that is larger, and compares the tentative PMTU to the existing
>   PMTU.
> 
> In other words, s/minimum IPv6 next hope MTU/IPv6 minimum link MTU/.
> That will make the terminology consistent with the rest of the document.

Yes, I agree.  Also removes the misspelled “hop”.

> 
> 2.) It is difficult to tell from Appendix B what has actually changed
> since RFC 1981. The detailed account of what was changed from one draft
> to the next has been very useful to the working group but will not be
> particularly helpful to readers of an archival document. I would
> therefore suggest that prior to publication as an RFC this Appendix
> should be replaced with an actual summary of the changes since RFC 1981.
> 
> I might note that this same point was made by Robert Sparks in his
> GEN-ART review of companion document draft-ietf-6man-rfc4291bis (see
> https://www.ietf.org/mail-archive/web/ipv6/current/msg26035.html):
> 
>> Appendix B looks like something groups normally ask the RFC Editor
>> to delete. If that was your intent, please add instructions to the
>> RFC Editor so they don't have to ask. If you planned to leave it, a
>> summary of the changes rather than a chronolog of what draft version
>> changes were made in would be much more useful to future readers.
>> (Such a summary would be welcome in any case.)
> 
> I am aware that preparing such a summary is a significant amount of
> work, and I am willing to send text should the editor so desire.

Thanks, I agree it’s a good idea.  I did that for rfc2460bis recently, and will work on that for rfc1981bis too.  I will send a draft copy to you to review prior publishing.

Thanks,
Bob


> 
> Thanks and regards,
> 
> Mike Heard
> 
> On Fri, 31 Mar 2017 10:32:02 -0500, Bob Hinden wrote:
>> Hi,
>> 
>> I published a new version of rfc1981bis (-05).  Links to the document below.
>> 
>> The changes in this version are based on comments in IETF last call reviews
>> by Gorry Fairhurst, Joe Touch, Susan Hares, Stewart Bryant, Rifaat
>> Shekh-Yusef, and Donald Eastlake.  Many thank to the reviewers as I think
>> the document is significantly improved, it is much better aligned with
>> current transport practice.
>> 
>> The changes include:
>> 
>>   o  Clarify that the purpose of PMTUD is to reduce the need
>>      for IPv6 Fragmentation.
>> 
>>   o  Added text to Introduction about effects on PMTUD when
>>      ICMPv6 messages are blocked.
>> 
>>   o  Clarified in Section 4. that nodes should validate the
>>      payload of ICMPv6 PTB messages per RFC4443.
>> 
>>   o  Removed text in Section 5.2 about the number of paths to a
>>      destination.
>> 
>>   o  Changed title of Section 5.4 to "Packetization layer
>>      actions".
>> 
>>   o  Clarified first paragraph in Section 5.4 to to cover all
>>      packetization layers, not just TCP.
>> 
>>   o  Clarified text in Section 5.4 to use normal retransmission
>>      methods.
>> 
>>   o  Add clarification to Note in Section 5.4 about
>>      retransmissions.
>> 
>>   o  Removed text in Section 5.4 that described 4.2BSD as it is
>>      now obsolete.
>> 
>>   o  Removed reference to TP4 in Section 5.5.
>> 
>>   o  Updated text in Section 5.5 about NFS including adding a
>>      current reference to NFS and removing obsolete text.
>> 
>>   o  Revised text in Section 6 to clarify first attack
>>      response.
>> 
>>   o  Added new text in Section 6 to clarify the effect of
>>      ICMPv6 filtering on PMTUD.
>> 
>>   o  Aligned terminology for the packetization layer
>>      terminology.
>> 
>>   o  Editorial changes.
>> 
>> A diff from the previous version can be found at:
>> 
>>   https://tools.ietf.org/rfcdiff?url2=draft-ietf-6man-rfc1981bis-05.txt
>> 
>> Please review.
>> 
>> This is part of the project to move the core IPv6 specifications to Internet
>> Standard.
>> 
>> Thanks,
>> Bob
>> 
>>> A new version of I-D, draft-ietf-6man-rfc1981bis-05.txt
>>> has been successfully submitted by Robert M. Hinden and posted to the
>>> IETF repository.
>>> 
>>> Name: draft-ietf-6man-rfc1981bis
>>> Revision: 05
>>> Title: Path MTU Discovery for IP version 6
>>> Document date: 2017-03-31
>>> Group: 6man
>>> Pages: 18
>>> URL:
>>> https://www.ietf.org/internet-drafts/draft-ietf-6man-rfc1981bis-05.txt
>>> Status:
>>> https://datatracker.ietf.org/doc/draft-ietf-6man-rfc1981bis/
>>> Htmlized:       https://tools.ietf.org/html/draft-ietf-6man-rfc1981bis-05
>>> Htmlized:
>>> https://datatracker.ietf.org/doc/html/draft-ietf-6man-rfc1981bis-05
>>> Diff:
>>> https://www.ietf.org/rfcdiff?url2=draft-ietf-6man-rfc1981bis-05
>>> 
>>> Abstract:
>>>  This document describes Path MTU Discovery for IP version 6.  It is
>>>  largely derived from RFC 1191, which describes Path MTU Discovery for
>>>  IP version 4.  It obsoletes RFC1981.