Last Call Review of draft-ietf-tsvwg-sctp-prpolicies-05

Request Review of draft-ietf-tsvwg-sctp-prpolicies
Requested rev. no specific revision (document currently at 07)
Type Last Call Review
Team Ops Directorate (opsdir)
Deadline 2014-12-01
Requested 2014-11-11
Authors Michael Tüxen, Robin Seggelmann, Randall Stewart, Salvatore Loreto
Draft last updated 2014-12-01
Completed reviews Genart Last Call review of -05 by Tom Taylor (diff)
Secdir Last Call review of -05 by Joseph Salowey (diff)
Opsdir Last Call review of -05 by Dan Romascanu (diff)
Assignment Reviewer Dan Romascanu
State Completed
Review review-ietf-tsvwg-sctp-prpolicies-05-opsdir-lc-romascanu-2014-12-01
Reviewed rev. 05 (document currently at 07)
Review result Has Issues
Review completed: 2014-12-01


I have reviewed this document as part of the Operational directorate's ongoing effort to review all IETF documents being processed by the IESG.  These comments  were written primarily for the benefit
 of the operational area directors.  Document editors and WG chairs should treat these comments just like any other last call comments.


Summary: Ready with issues


Document Ready, but Operational and Management considerations missing.


As the Abstract says:


   This document defines two additional policies for the Partial

   Reliability Extension of the Stream Control Transmission Protocol

   (PR-SCTP) allowing to limit the number of retransmissions or to

   prioritize user messages for more efficient send buffer usage.

Although this document defines an extension of an existing protocol, there are no explicit considerations about operations and management. The OPS and Transport ADs should decide whether this
 is an issue to be addressed before the document is approved. 


Specifically, following the checklists in RFC 5707, Appendix A:




Deployment is not discussed, although there is text that says that the Limited Retransmissions Policy can be used with data channels in the
 WebRTC protocol stack, and that the Priority Policy can be used in the IPFIX protocol stack



Installation and initial setup is not discussed



Migration Path does not seem to apply



There is information about RFC 3758 being mandatory to implement in order to implement these extensions



The impact on the network operation is not discussed explicitly



There are no explicit suggestions about verifying correct operations, although one can understand that the socket options described in sections
 4.3, 4.4, 4.5 are useful to determine stream specific status, association specific status, and to get and set the PR-SCTP support



Interoperability does not seem to apply excepting the requirement to implement RFC 3758



There is no information about faults or threshold conditions to be reported



Configuration is not discussed, it may not apply, but it would be good to state this



There are no manageability considerations of any kind


One terminology issue is worth being considered: The document speaks about two additional policies for PR-SCTP. However, the RFC defining PR-SCTP (RFC 3758) does not use
 the term policy at all. Timed Reliability which in this document is called a ‘policy’ is described in RFC 3758 as a ‘service to upper layer’. It would be good to either align terminology, or to explain that the term policy used here corresponds to the ‘service’
 described in RFC 3758.