Hi,

Many Thanks Adrian - Authors, could you please address the points listed below ?

Thanks.

JP.

On Mar 30, 2012, at 12:11 AM, Adrian Farrel wrote:

> Please accept this comment as an individual comment like all the rest.
>  
> I have some reservations about adopting this document as a WG draft, but will 
> not register to stand in its way.
>  
> I understand the motive for this work and, indeed, it fills a hole in the 
> protocol spec.
>  
> I do hope that the authors are building it for shipping equipment and 
> deployment. If not, would they please consider whether it should be 
> experimental?
>  
> Here are some comments based on a very light review. I should probably read 
> the document properly some day.
>  
> I am concerned that this document changes the definition and intent contained 
> in RFC 5440. In my opinion the authors of 5440, and the WG at the time, wen 
> to some lengths to tie the content of objects in PCEP to the same definitions 
> found in RFCs 3209, 3473 and 3477. At the same time, definitions of 
> subobjects for path definition, should also pay attention to RFCs 4874 and 
> 4920. The intention is to not define more subobjects than needed and to keep 
> registries aligned.



>  
> It is also worth noting how 4920  handles 2 and 4 octet AS numbers and that 
> there is overlap in the definition of AS number subobjects with 
> draft-zhang-pce-hierarchy-extensions-01
>  
> In this light and on careful reading, the IANA section is somewhat broken and 
> confused about what should be in the registry it is creating.
>  
> But I am also unsure why a new IRO type is needed. Surely the domain sequence 
> that is used in the computation is also the domain sequence for the path that 
> the LSP will take. This feeds on the points below.
>  
> The algorithm in 3.4:
> - assumes only area IDs and AS numbers
> - assumes that a PCE knows at least one PCE responsible for each of
>    its neighboring domains
>  
> I would like the authors to take care that the identity of a boundary node 
> does not uniquely identify a next-hop domain (even if it may be successfully 
> used for domain routing given the knowledge of the next domain, next boundary 
> node, or egress node) and the text should not imply that it does. This is 
> hidden at the end of 3.4 some time after the  boundary node/link discussion.
>  
> Shouldn't you allow "loose" hops in the domain path? (i.e. gaps between 
> domains).
>  
> Can I also mix other concepts with the domain path? What about a consistent 
> lambda, or a core node that needs to be on the path?
>  
> In 3.5.7 I don't see that the domain sequence is necessarily an alternative 
> to the PCE sequence. There are cases where even with a domain sequence, a PCE 
> sequence is important.
>  
> In 3.5.7 you have:
>       All PCE must be aware of all other PCEs in all domain for PCE-
>       Sequence.
> This is false. Although it is true that a PCE in one domain must be able to 
> route to the IP address of a PCE in a neighboring domain.
>  
> In 3.5.7 you have:
>       There maybe multiple PCE in a domain, the selection of PCE should
>       not be made at the PCC/PCE(1).  This decision is made only at the
>       neighboring PCE which is aware of state of PCEs via notification
>       messages
> There are four points here:
> 1. These are unsubstantiated assertions rather than reasons.
> 2. All neighboring PCEs are sending each other notification messages?
> 3. PCE choice may be based on capabilities, not just being up
> 4. In HPCE, it is quite reasonable for the parent to select the children
>  
> Section 5 will need loads of work because the domain sequence (even for 
> inclusion, not reporting) provides information valuable to an attacker.
>  
> I am sure the management considerations can be added within the WG process.
>  
> Thanks,
> Adrian
>  
>  
> From: [email protected] [mailto:[email protected]] On Behalf Of JP 
> Vasseur
> Sent: 29 March 2012 17:30
> To: [email protected]
> Subject: [Pce] Adopting draft-dhody-pce-pcep-domain-sequence-02 as a new PCE 
> WG
>  
> Dear all,
>  
> We had a pretty strong support for adopting 
> draft-dhody-pce-pcep-domain-sequence-02 a PCE Working Group during our PCE WG 
> meeting but
> as usual we'd like to confirm on the mailing list.
>  
> Could you please let us know if you are in favor/opposed to adopting 
> draft-dhody-pce-pcep-domain-sequence-02 as a PCE WG Document ?
>  
> Thanks.
>  
> JP and Julien.

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