Re: [mpls] MPLS-RT review of draft-atlas-mpls-te-express-path

[Sriganesh Kini <[e-mail]>]

Hello Loa,

Overall I think the document is addressing a useful problem but needs an
update to make it more coherent and sound before going to WG acceptance
call.

My comments are listed below -

1. The filename "mpls-te-express-path" has no correlation to the title and
content of the draft. I would suggest a more appropriate filename such as
"mpls-te-path-selection-mechanism".

2. The "Short Title" should be changed to reflect that this is a path
selection mechanism. Suggest "Simple path selection mechanism".

3. Abstract last sentence is better worded as "This document specifies a
computationally simpler mechanism to select performance-constraint-bounded
paths by using performance data advertised via an IGP"

4. It is not clear why there is a dependence on the performance data being
advertised via IGP. Can't it come from other sources. E.g. a management
system ?

5. The limitations of the path computed due to the scope of link-state
advertisements should be stated. E.g. if the referenced docs for IGP
extensions have area scoped performance-data advertisements, then the
head-end may not be able to compute paths beyond the area.

6. Section 1.1 enum 3 - s/perforance/performance

7. Section 1.1 enum 4 suggest s/configuration/constraints

8. Section 2.1 - Need a reference for CSPF algorithm being referred to. It
may be of value to write an appendix that gives pseudocode on how the
constraint checking is inserted into the CSPF.

9. Section 2.1 - In the paragraph starting with "This is illustrated as
follows.". It may be useful to state that there are cases where all the
links of X when explored may violate the bounded constraint the algorithm
should backtrack from the point where the bounded constraint was still
being satisfied.

10. Sec 2.3.3 - Is this an optimization of when to re-optimize ? Because
any link coming out of Anomalous may provide a better path, not just a
link that caused LSPs to change when it went to the Anomalous state. If
so, it may be useful to state it.

Also this document should be posted to the PCE WG for comments.


Thanks
-- Sri






On 4/5/13 9:50 PM, "Loa Andersson" <[e-mail]> wrote:

>Xiaohu, Sri, Rajiv and Pranjal,
>
>You have been selected as an MPLS Review team reviewers for
>draft-atlas-mpls-te-express-path-02.
>
>Note to authors: You have been CC'd on this email so that you can know
>that this review is going on. However, please do not review your own
>document.
>
>Reviews should comment on whether the document is coherent, is it
>useful (ie, is it likely to be actually useful in operational
>networks), and is the document technically sound?  We are interested
>in knowing whether the document is ready to be considered for WG
>adoption (ie, it doesn't have to be perfect at this point, but should be
>a good start).
>
>Reviews should be sent to the document authors, WG co-chairs and
>WG secretary, and CC'd to the MPLS WG email list. If necessary, comments
>may be sent privately to only the WG chairs.
>
>Are you able to review this draft by April 20, 2013?
>
>Thanks, Loa
>(as MPLS WG chair)
>
>/Loa
>-- 
>
>
>Loa Andersson                        email: [e-mail]
>Senior MPLS Expert                          [e-mail]
>Huawei Technologies (consultant)     phone: [phone]