Carl Knutsson | 3 Feb 2011 14:35
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Re: [Technical Errata Reported] RFC5225 (2703)

Lars, others,

I have had an on-list discussion with Sasha and an off-list with
Kristofer and I have come up with the suggested correction. The actual
details of the suggestion in the errata haven't been discussed. So I
would like people to review the errata. Comments from the authors would
also be appreciated.

There are three things that I'd like to point out here:

1) There is no ip_id_behavior control field in the FN of RFC 5225. Only
ip_id_behavior_innermost and ip_id_behavior_outer.

2) Not to include the control field for outer IPv6 headers is the actual
bug fix. There does not exist any ip_id_behavior_outer control field in
the FN for ipv6 (it does for ipv4).

3) Excluding the control field for the innermost IPv6 header may be
considered a change and not a correction, but since the whole business
with the ip_id_behavior is not crystal clear...

So especially number 3) is up for discussion and also my suggestion for
the Corrected Text.

cheers,

/Calle

On 02/03/2011 01:52 PM, Lars Eggert wrote:
> Based on the ongoing discussion, I assume the community consensus is to approve this?
> 
> On 2011-2-3, at 14:22, RFC Errata System wrote:
> 
>>
>> The following errata report has been submitted for RFC5225,
>> "RObust Header Compression Version 2 (ROHCv2): Profiles for RTP, UDP, IP, ESP and UDP-Lite".
>>
>> --------------------------------------
>> You may review the report below and at:
>> http://www.rfc-editor.org/errata_search.php?rfc=5225&eid=2703
>>
>> --------------------------------------
>> Type: Technical
>> Reported by: Carl Knutsson <carl.knutsson <at> effnet.com>
>>
>> Section: 6.6.11
>>
>> Original Text
>> -------------
>> o  ip_id_behavior, one octet for each IP header in the compressible
>>
>>   header chain starting from the outermost header.  Each octet
>>
>>   consists of 2 bits padded with 6 MSBs of zeroes.
>>
>> Corrected Text
>> --------------
>> o  ip_id_behavior_outer, one octet for each IPv4 header except the
>>
>>   innermost in the compressible header chain starting from the outermost 
>>
>>   header. Each octet consists of 2 bits padded with 6 MSBs of zeroes.
>>
>>
>>
>> o  ip_id_behavior_innermost, one octet if the innermost header is an 
>>
>>   IPv4 header. The octet consists of 2 bits padded with 6 MSBs of zeroes.
>>
>> Notes
>> -----
>> There is no control field called ip_ip_behavior in the document. There are two control fields related to
IP-ID behavior, ip_id_behavior_innermost and ip_id_behavior_outer. For IPv6, only the
ip_id_behavior_innermost field exists and its value is always IP_ID_BEHAVIOR_RANDOM according to the
FN. This makes it impossible to include ip_id_behavior_outer when calculating the crc for IPv6 headers.
Furthermore, since the ip_id_behavior_innermost is constant it makes no sense to include it in the crc calculation.
>>
>> Instructions:
>> -------------
>> This errata is currently posted as "Reported". If necessary, please
>> use "Reply All" to discuss whether it should be verified or
>> rejected. When a decision is reached, the verifying party (IESG)
>> can log in to change the status and edit the report, if necessary. 
>>
>> --------------------------------------
>> RFC5225 (draft-ietf-rohc-rfc3095bis-rohcv2-profiles-06)
>> --------------------------------------
>> Title               : RObust Header Compression Version 2 (ROHCv2): Profiles for RTP, UDP, IP, ESP and UDP-Lite
>> Publication Date    : April 2008
>> Author(s)           : G. Pelletier, K. Sandlund
>> Category            : PROPOSED STANDARD
>> Source              : Robust Header Compression
>> Area                : Transport
>> Stream              : IETF
>> Verifying Party     : IESG
> 

Gmane