Thank you.

> On Jan 26, 2015, at 5:05 PM, Brian E Carpenter <[email protected]> 
> wrote:
> 
> Looks good to me, thanks.
> 
>   Brian
> 
> On 27/01/2015 09:36, Carlos Pignataro (cpignata) wrote:
>> Hi, Brian,
>> 
>> On Jan 25, 2015, at 4:47 PM, Brian E Carpenter 
>> <[email protected]<mailto:[email protected]>> wrote:
>> 
>> Hi Carlos,
>> 
>> On 26/01/2015 08:49, Carlos Pignataro (cpignata) wrote:
>> Hi, Brian,
>> 
>> Thanks for your review! Please see inline.
>> 
>> On Jan 25, 2015, at 2:29 PM, Brian E Carpenter 
>> <[email protected]<mailto:[email protected]>> wrote:
>> 
>> I am the assigned Gen-ART reviewer for this draft. For background on
>> Gen-ART, please see the FAQ at
>> <http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>.
>> 
>> Please resolve these comments along with any other Last Call comments
>> you may receive.
>> 
>> Document: draft-ietf-mpls-oam-ipv6-rao-02.txt
>> Reviewer: Brian Carpenter
>> Review Date: 2015-01-26
>> IETF LC End Date: 2015-02-04
>> IESG Telechat date:
>> 
>> Summary: Almost ready
>> --------
>> 
>> Minor issues:
>> -------------
>> 
>> 1. Hop-by-hop options, and therefore Router Alert, are well known to
>> cause a serious performance issue or are simply ignored by many
>> routers (as warned in http://tools.ietf.org/html/rfc7045#section-2.2).
>> A pointer to that warning would be appropriate.
>> 
>> 
>> I do not believe this concern is very applicable to the MPLS OAM RAO. The 
>> whole point of RAO in an MPLS LSP is to be intercept the packet and punt it 
>> to a slow path, and it is not injected back. The MPLS OAM Router Alert 
>> option is invisible to the MPLS Label-switched hops, and when the LSP 
>> finishes, it is only processed once.
>> 
>> I am also not sure I understand the suggested action behind this comment. 
>> Are you suggesting we add a pointer to that Section, or that exact paragraph 
>> to the Security Considerations?
>> 
>> Well, maybe what you could do is add a statement that this type of RAO
>> is not subject to the problem of being ignored, because the appropriate
>> router will process it (on the slow path) by design. The generic problem
>> is that HbH options might be ignored even if the designer assumes otherwise,
>> which is why we added the warning in RFC 7045, and you're saying that
>> problem doesn't apply here.
>> 
>> Sounds good — I added the following paragraph (and Informational reference). 
>> All, can you please review?
>> 
>>   IPv6 packets containing the MPLS OAM Router Alert Option are
>>   encapsulated with an MPLS Header and not expected to be inspected by
>>   every label switched hop within an MPLS LSP.  Consequently, this
>>   value of the Router Alert Option will be processed by the appropriate
>>   router and is not subject to the problem of being ignored as
>>   described in Section 2.2 of [RFC7045].
>> 
>> 
>> 
>> 2. I'm a bit surprised to realise that new definitions of Router Alert
>> options are not routinely notified to the 6MAN WG.
>> 
>> We had run this through 6MAN, both on list and presenting twice in IETF 
>> meetings.
>> 
>> I must have been asleep, sorry!
>> 
>> 
>> No worries, thanks for the review!
>> 
>> — Carlos.
>> 
>>  Brian
>> 
>> Thanks!
>> 
>> Carlos.
>> 
> 

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