Subject: [PWE3] AD review of draft-ietf-pwe3-p2mp-pw-requirements

From: "Adrian Farrel" <[email-masked]>
Date: Thu, 13 Mar 2014 14:45:40 -0000

Hi,

I have done my usual review as AD in support of the publication request
for this document. This is now a very solid document : all credit to the
authors and to Stewart's guidance.

As I have only a few minor nits with the text (shown below) I will start 
the IETF last call and raise the issues there. You can address them 
together with any other points that are raised during the last call.

Thanks for the work,
Adrian

===

PSN needs to be expanded in the title, Abstract, and Introduction.

Please check for other acronyms like OAM.

---

Since this is not a protocol specification, the RFC 2119 language does
not apply in the way described in RFC 2119. I suggest you replace 
Section 1.3 with something like...

   Although this is a requirements specification not a protocol 
   specification, the key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
   "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and 
   "OPTIONAL" in this document are to be interpreted to apply to 
   protocol solutions designed to meet these requirements as described
   in [RFC2119] .

---

I have a question about the architecture and model shown in Figure 1.
Can the P2MP PW branch at an egress PE by having multiple attached ACs
leading to different CEs?

Perhaps this does not count as a branch in the PW, but it is a branch in 
the service.

---

In Section 3.2

s/P-to-MP MPLS LSP/P2MP MPLS LSP/

---

Section 3.4.2 has...

   The Root PE and Leaf PEs of a P2MP PW MUST be configured with the
   same PW type as defined in [RFC4446] for P2P PW.  In case of a
   different type, a PE MUST abort attempts to establish the P2MP PW.

That seems a little drastic. Do you mean "MUST abort attempts to 
attach the leaf PE to the PW"?

Similarly in 3.4.3.

---

Section 4 might usefully refer back to the discussion of OAM.

---

Section 5 is fine, but it is interesting to consider

   A solution MUST NOT allow a P2MP PW to be established to PEs that do
   not support P2MP PW functionality.  It MUST have a mechanism to
   report an error for incompatible PEs.

Does an egress PE even need to know that it is attached to a P2MP PW
rather than a P2P PW?