Re: [mpls] AD review of Soft Preemtion work

[JP Vasseur <[e-mail]>]

Great plan, many thanks. Will be done before end of this week.

Thanks.

JP.

On Jul 27, 2009, at 10:19 AM, Adrian Farrel wrote:

> OK JP,
>
> Complete the discussions with the other authors, then prepare the  
> text as RFC Editor instructions. If they look OK I will just post  
> them. If they look too large, you can use them to make the changes  
> yourselves.
>
> Thanks,
> Adrian
> ----- Original Message ----- From: "JP Vasseur" <[e-mail]>
> To: "Adrian Farrel" <[e-mail]>; "Lou Berger" <[e-mail] 
> >; "Deborah Beebe (dbeebe)" <[e-mail]>
> Cc: <[e-mail]>; <[e-mail] 
> >; <[e-mail]>; <[e-mail] 
> >; <[e-mail]>; <[e-mail]>
> Sent: Sunday, July 26, 2009 9:12 PM
> Subject: Re: AD review of Soft Preemtion work
>
>
>> Hi Adrian,
>>
>> I basically agree with all your comments ...
>> Few comments/replies:
>> With regards to the path-error ID, it is IMO MPLS focussed, Lou/  
>> Deborah may want to chime in.
>> I definitely agree to insert of reference to 5511. For the other   
>> changes, I tend to think that they could be addressed with an  
>> editor  note but your call of course.
>>
>> Thanks.
>>
>> JP.
>>
>> On Jul 26, 2009, at 1:32 PM, Adrian Farrel wrote:
>>
>>> Hi,
>>>
>>> I've been reading draft-ietf-mpls-3209-patherr-04.txt,
>>>
>>> prior to kicking off IETF last call.
>>>
>>> I don't have many questions...
>>>
>>> The Abstract and Introduction to draft-ietf-mpls-3209- 
>>> patherr-04.txt explicitly call out MPLS when discussing RSVP-TE  
>>> PathErr messages.  But they do not mention GMPLS. In fact, the  
>>> only reference to  RFC3473 is in section 2.2. I think that the  
>>> text needs to be clear  on whether or not it is intended to apply  
>>> to GMPLS signaling. This  obviously affects how the document is  
>>> read and applied, and should  not be left for people to assume  
>>> (one way or the other).
>>>
>>> draft-ietf-mpls-3209-patherr-04.txt uses some BNF (copied from RFC  
>>> 2205). New "rules" require that any document that uses a formal   
>>> language includes a reference to the definition of the formal   
>>> language. Your choice here is:
>>> - leave out the text copy from 2205
>>> - insert a reference to RFC 5511
>>>
>>> draft-ietf-mpls-3209-patherr-04.txt Page 4
>>> Additionally, PathErr messages may be used in two circumstances:
>>> Strike "Additionally,"
>>>
>>> The RFC Editor will require the first section of draft-ietf-mpls-  
>>> soft-preemption-17.txt to be the Introduction. I think you can   
>>> simply re-order the sections you already have, and expand the   
>>> acronyms in the Introduction section.
>>>
>>> I am trying to not re-open my mailing list discussions of draft- 
>>> ietf- mpls-soft-preemption-17.txt from the last couple of  
>>> years. :-) In section 6.1 you have
>>> For each preempted TE LSP, instead of sending an RSVP Path Tear
>>> message after the receipt of an RSVP PathErr message notifying a
>>> fatal action as documented in [I-D.ietf-mpls-3209-patherr] upon
>>> preemption as with hard preemption (which would result in an
>>> immediate traffic disruption for the preempted TE LSP), the
>>> preempting node's local bandwidth accounting for the preempted TE  
>>> LSP
>>> is zeroed and a PathErr with error code "Reroute" and a error value
>>> "Reroute request soft preemption" for that TE LSP is issued upstream
>>> toward the head-end LSR.
>>> I can't parse this single-sentence paragraph. Can you look at how  
>>> to break it up? I think the node being described is the  
>>> preempting  node. But the preempting node does not receive a  
>>> PathErr so the  first part of the sentence confuses me.
>>>
>>> draft-ietf-mpls-soft-preemption-17.txt section 6.1
>>> Should a refresh event for a soft preempted TE LSP arrive before the
>>> soft preemption timer expires, the soft preempting node MUST  
>>> continue
>>> to refresh the TE LSP.
>>> This is the first mention of a soft preemption timer. I think you   
>>> need to swap the text around so the definition of the timer (2  
>>> paras  later) is introduced first.
>>>
>>> draft-ietf-mpls-soft-preemption-17.txt Section 13.2
>>> [I-D.ietf-mpls-3209-patherr] should be a Normative reference
>>>
>>>
>>> I have marked the documents as:
>>> draft-ietf-mpls-soft-preemption  "AD Evaluation : Revised I-D  
>>> Needed"
>>> draft-ietf-mpls-3209-patherr  "AD Evaluation : Revised I-D Needed"
>>> draft-ietf-mpls-gmpls-lsp-reroute  "AD Evaluation : External Party"
>>>
>>> I'm willing to discuss:
>>> a. whether these changes are needed
>>> b. whether the changes need a respin or an RFC Editor note
>>>
>>> Cheers,
>>> Adrian
>>>
>>>
>>>
>>
>
>