Re: [CCAMP] Review Request For Changes in draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04.txt

[[e-mail]]

Lou, see response lined with <fei1>

Thanks

Fei



Lou Berger <[e-mail]> 
2012-08-27 03:45

收件人
[e-mail]
抄送
"[e-mail]" <[e-mail]>, "Rakesh Gandhi (rgandhi)" 
<[e-mail]>
主题
Re: [CCAMP] Review Request For Changes in 
draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04.txt








On 8/25/2012 11:43 PM, [e-mail] wrote:
> 
> Hi Lou,
> 
> Thanks for your detailed review, snipped the others, see inline with 
<fei>
> 
> Well I (as chair) had asked in Vancouver that the authors of
> rsvpte-ext-tunnel-num propose some language *on the list* that would
> merge the functionality defined in that document into the WG document.
> The mailing list discussion concluded with Fei stating that he want to
> keep the drafts separate, which certainly is his call (as one is an
> individual draft).  So to be clear, I have not requested any references
> to rsvpte-ext-tunnel-num in the WG draft.
> 
> <Fei> Sure, this part is also informational and there is no new
> mechanism introduced here. :)

Given the recent discussion (on co-routed) I don't think the reference
makes any sense given the scope of rsvpte-ext-tunnel-num propose is
co-routed bidirectional which is currently 100% out of scope of this
document.


<fei1>Ok, I agree with your statement, and the text just wants to show 
that
the same procedure defined in rsvpte-ext-tunnel-num (which is scoped to 
corouted bidirectional LSP) can be used here also if necessary. 

Do you have any advice how to organize this paragraph?

(1)Remove the cited reference and delete this paragraph, just ignore this
issue.

(2)Remove the cited reference and keep this paragraph (with revision)

If it is (2), can you help give some words?

Or other schemes?


> 
> This section does highlight the issue of how remote global_ID can be
> learned in the interdomain case.  I think the stated solution doesn't
> work with your current assignment approach, e.g., consider the case when
> the lower IP address is the egress of the initial LSP...
> 
> <Fei> For the singled sided provisioning model, the initial LSP source
> address (Association Source)and global_ID are pushed into the EA
> objects, so the ingress can learn the global ID of the peer node by the
> defined Association Type "LSP Identifiers" which is carried in the Path
> message and back in the Resv messages.

this implies a rule of the lower IP address always signaling its LSP
first.  Seems a bit arbitrary to me, and isn't reflected in the current
text.  How about just following the administrative approach being
discussed with Rakesh in the other thread on the same topic?

<fei1>The Association Source could be the lower IP address or the higher 
IP address in
single sided provisioning model, which is depending on the touch point and
different from the double sided (the lower IP address always wins). The 
administrative
approach can integrate both models, will be a good idea.


Lou

> 
> For the doubled sided provisioning model, since the lower IP address
> (Association Source) wins the tie breaker, the Association object with
> Association Type "LSP Identifiers" can be pushed into the Path message
> by the lower IP address initial LSP can carry back the global_ID of the
> higher IP address in the Resv message.
> 
> In other words, the Association object with Association Tyep "LSP
> Identifiers" are always pushed by the Association Source into the Path
> message can carried back in the Resv message with the peer node's
> global_ID in both provisioning model if necessary.
> 
> Do you think the currently description needs more clarification words?
> 
> Thanks
> 
> Fei
> 
> 
> *Lou Berger <[e-mail]>*
> 发件人:  [e-mail]
> 
> 2012-08-25 01:55
> 
> 
> 收件人
>                "Rakesh Gandhi (rgandhi)" <[e-mail]>
> 抄送
>                "[e-mail]" <[e-mail]>
> 主题
>                Re: [CCAMP] Review Request For Changes in 
>  draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04.txt
> 
> 
> 
> 
> 
> 
> 
> 
> Rakesh,
> 
> Speaking as a WG participant, and ignoring changes 4 and 5 as you plan
> to revert these:
> 
> On 8/23/2012 12:20 PM, Rakesh Gandhi (rgandhi) wrote:
>> Dear WG,
>>
>> We like to request a review from the WG on the changes in version 04
> of the draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp compared to
> version 03.
>>
>> The majority of the proposed changes are around the format and how to
> populate the extended association object as listed below.
>>
>> Note: Based on the feedbacks received so far, changes for items 4 and
> 5 below will be reverted.
>>
>> 1. Association-ID:
>> It was not clear from reading the version 03 of the draft how this
> field is populated in the extended association object. New version 04
> proposes to populate this field from the locally provisioned value. As
> this value is identically provisioned on both ends, it provides a field
> to tie the two (forward and reverse) LSPs on end-points.
>>
> 
>> 2. IPv4 association source:
>> New version 04 adds a tie breaker rule for double sided provisioned 
LSPs.
>>
>> 3. Global association source:
>> New version clarifies the usage for this field siting information from
> RFC6370 and other mentioned drafts. No new rule added.
>>
> 
> [4 and 5 removed form mail as to be reverted]
> 
>>
>> 6. Extended Association ID (Address):
>> New version 04 proposes to use an IP address as extended association
> ID (address) as an additional identifier. Previous version 03 defines a
> variable length field but did not mention what parameters can be added
> there.
>> A tie breaker rule is defined for double sided provisioned value.
>>
> 
> Assuming changes 1, 2, and 6, how is uniqueness (of the association ID
> field) guaranteed?
> 
>> 7. Path Protection object:
>> Version 03 of the draft vaguely mentioned and assumed of using
> protection object for path protection. New version 04 adds some texts to
> clarify it, no new rule is added.
>>
> 
> I think providing informative text on interactions of this document with
> the various defined recovery (4872 and 4872) and reroute (4090)
> mechanisms is a really good idea.  That said, I found this section a bit
> opaque.  Ignoring the wordsmithing, what specific points are you trying
> to make?
> 
>> 8. Auto-tunnel mesh:
>> New version 04 adds a section to elaborate on a use case for
> auto-tunnel mesh. This is added as an FYI and can be removed if WG
> thinks so.
>>
> 
> How is the association id field value selected in this case?
> 
> 
>> 9. Clarification for Inter-AS LSPs:
>> I believe there was an email exchange between Lou and Fei to clarify
> the relationship with draft I-D,
> draft-zhang-ccamp-mpls-tp-rsvpte-ext-tunnel-num. A section is added in
> version-04 to address this. Please review the added text.
>>
> 
> Well I (as chair) had asked in Vancouver that the authors of
> rsvpte-ext-tunnel-num propose some language *on the list* that would
> merge the functionality defined in that document into the WG document.
> The mailing list discussion concluded with Fei stating that he want to
> keep the drafts separate, which certainly is his call (as one is an
> individual draft).  So to be clear, I have not requested any references
> to rsvpte-ext-tunnel-num in the WG draft.
> 
> This section does highlight the issue of how remote global_ID can be
> learned in the interdomain case.  I think the stated solution doesn't
> work with your current assignment approach, e.g., consider the case when
> the lower IP address is the egress of the initial LSP...
> 
> Lou
> 
> 
>> Please advise us on above changes. Based on the consensus, we will
> update the draft accordingly.
>>
>> Thanks,
>> Rakesh
>> 
>>
>> -----Original Message-----
>> From: [e-mail] [mailto:[e-mail]]
>> Sent: Wednesday, August 15, 2012 10:53 AM
>> To: Rakesh Gandhi (rgandhi)
>> Cc: [e-mail]; [e-mail]
>> Subject: New Version Notification for
> draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04.txt
>>
>>
>> A new version of I-D,
> draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04.txt
>> has been successfully submitted by Rakesh Gandhi and posted to the
> IETF repository.
>>
>> Filename: 
>  draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp
>> Revision:                  04
>> Title:                                   RSVP-TE Extensions for
> Associated Bidirectional LSPs
>> Creation date:                  2012-08-15
>> WG ID:                                   ccamp
>> Number of pages: 17
>> URL: 
> 
http://www.ietf.org/internet-drafts/draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04.txt

>> Status: 
>  
http://datatracker.ietf.org/doc/draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp

>> Htmlized: 
>  
http://tools.ietf.org/html/draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04

>> Diff: 
>  
http://www.ietf.org/rfcdiff?url2=draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-04

>>
>> Abstract:
>>    The MPLS Transport Profile (MPLS-TP) requirements document 
[RFC5654],
>>    describes that MPLS-TP MUST support associated bidirectional point-
>>    to-point LSPs.
>>
>>    This document provides a method to bind two unidirectional Label
>>    Switched Paths (LSPs) into an associated bidirectional LSP.  The
>>    association is achieved by defining the new Association Type in the
>>    Extended ASSOCIATION object.
>>
>> 
> 
>>
>>
>> The IETF Secretariat
>>
>> _______________________________________________
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>> [e-mail]
>> https://www.ietf.org/mailman/listinfo/ccamp
>>
>>
>>
>>
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