Re: [v6ops] new draft: draft-taylor-v6ops-fragdrop

[Bob Hinden <[e-mail]>]

On Nov 8, 2012, at 2:05 PM, Ole Trøan wrote:

> Joe,
> 
>> There's remains other problematic language in 2460, however:
>> 
>>  Each extension header should occur at most once, except for the
>>  Destination Options header which should occur at most twice (once
>>  before a Routing header and once before the upper-layer header).
>> 
>> So it still seems open to have more than one HBH header, which certainly complicates things even though they'd be clearly marked.
> 
> I don't see how you can read that to imply you can have more than one Hop-by-Hop extension header.
> my reading (and what I think the _intention_ of the text was) is that there can only be one Hop-By-Hop extension header, and
> that the HBH header must be the first extension header in the chain. this way routers only need to check the Next Header field
> for the value of 0.

+1

Bob