Dhruv,

Thank you for the review. Please see answers inline below ###.

Ina

From: pce-boun...@ietf.org [mailto:pce-boun...@ietf.org] On Behalf Of Dhruv 
Dhody
Sent: Monday, March 11, 2013 8:03 AM
To: pce@ietf.org
Subject: [Pce] Comments on draft-ietf-pce-stateful-pce-02

Hi,

Please find the review comments for this draft (there is some overlap with 
comments from Jon, Cyril etc)

Major Comments:
(1) State synchronisation:
a. PCE should determine the synchronisation is over as soon as possible, as 
updates, request etc are blocked during synchronisation. Maybe the last report 
message can have SYNC=0 (similar to F - fragmentation bit in RP object) or as 
Jon suggested an empty report but then the RBNF of PCRpt should support it.
### Please see version 03 of the draft.

b. I also dont like the use of word 'purge' with respect to old or stale 
entries during PCEP session up/down. A mechanism to mark LSP entries as stale 
and waiting for them to be refreshed after session up and deleted (or 'purged') 
only after some timer expiry.
### Please see version 03 of the draft.


(2) The PCRpt Message:
<state-report> ::= <LSP>[<path-list>] Where: <path-list>::=<path>[<path-list>]. 
Is this to specify primary and backup? In which case the status of the paths 
needs to reported separately in case of standby but we have only one LSP object 
here to specify the operational status. Also LSP-ID of primary and backup would 
be different.

Also applicable to PCUpd message.
I feel the backup path should be updated and reported separately with each 
having there own encoding for LSP object.
### Clarification on backup paths will be done in the protection doc. I agree 
with you the text needs to be cleaned up in the base spec, will do so in 04.

(3) Node Identifier TLV
PCC may use address that survives the session restart (Loopback, MPLS LSR-ID 
etc), i suggest we mention this in the document and provide guidance to 
implementers to do this if possible.
### the node-id (now renamed to predundancy-group-id) will be further clarified 
in version 04

(4) LSP Object:
a. What is relationship between the LSP-ID in LSP object and the LSP-ID in LSP 
Identifier TLVs?
### The lsp-id in the lsp object was renamed to plsp-id to avoid such confusion.

b. There is no mechanism to report the 'pending' state right now? O-Bit as zero 
will mean down, not pending.
### The O-bit will be revisited in version 04.

(5) Make-Before-Break:
There is a need to clarify how MBB is achieved, what is the LSP-ID in case of 
updates and reports?
### Please see version 03.


Minor Comments:
(1) Abstract/Introduction
There is a consistent use of phrase "between and across PCEP sessions". Can you 
clarify?
### LSPs may move from one PCE to another.

(2) Re-look the terminology section as some terms are no longer in the document.
### Could you send the correction?

(3) LSP Protection
In case of delegated PCE, the desired protection may also be configured at PCC 
and the active stateful PCE should support it, the stateful PCE having full 
control over the protection / restoration settings can only be achieved with 
instantiation capability and should be out of scope from this document.
### The whole discussion on protection belongs in a separate document.

(4) Delegation
a. The wording "an LSP may be delegated to one or more PCEs." .. this is 
incorrect, from the reading it looks as if this is happening at the same time.
### To a single PCE, text is clarified in 03.

b. Active stateful PCE LSP Update (sec 5.6.2)
OLD:
A PCC may choose to compress LSP State Updates to only reflect the most up to 
date state, as discussed in the previous section.
NEW:
A PCC may choose to compress LSP State Reports to only reflect the most up to 
date state, as discussed in the previous section.
### Actually, I think we mean updates, not reports (if receiving multiple 
updates, may choose to do state compression during processing)

(5) Symbolic Path Name TLV
The length of this TLV must be greater then 0 as well as multiple of four.
### I think this is not necessary to specify in words, the figure should be 
sufficient.

(6) LSP state DB version TLV (page 40, para 2)
"Since a PCE does not send LSP updates to a PCC, a PCC should never encounter 
this TLV". LSP updates here can be easily confused with the PCUpd messages. 
Kindly reword this.
### Will do.

Regards,
Dhruv
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