Skip to main content

TCP and Stream Control Transmission Protocol (SCTP) RTO Restart
draft-ietf-tcpm-rtorestart-10

Yes

(Martin Stiemerling)

No Objection

(Alia Atlas)
(Alvaro Retana)
(Ben Campbell)
(Deborah Brungard)
(Jari Arkko)
(Kathleen Moriarty)
(Stephen Farrell)
(Terry Manderson)

Note: This ballot was opened for revision 08 and is now closed.

Martin Stiemerling Former IESG member
Yes
Yes (for -08) Unknown

                            
Spencer Dawkins Former IESG member
Yes
Yes (2015-10-14 for -08) Unknown
Thanks for producing this. It looks helpful.

I had a few comments you might consider.

Overall - I'm reading "restart the RTO timer" and its variations as an action that would *increase* the delay before retransmission, but that's backwards - RTOR is an action that can *decrease* the delay before retransmission. I suspect I'm not the only reader who would be confused on this. The word "restart" is pervasive in this document (I counted 48 occurances, including page headers), so I can't reasonably ask about using a different term, but I'm wondering if it would be clearer if the abstract said something like 

OLD

The modification, RTO Restart (RTOR), allows the
   transport to restart its retransmission timer so that the effective
   RTO becomes more aggressive in situations where fast retransmit
   cannot be used.
   
NEW

The modification, RTO Restart (RTOR), allows the
   transport to restart its retransmission timer using a smaller delay,
   so that the effective 
   RTO becomes more aggressive in situations where fast retransmit
   cannot be used.

In the Introduction,

   Second, when a sender
   receives duplicate acknowledgments, or similar information via
   selective acknowledgments, the fast retransmit algorithm infers data
   loss and triggers a retransmission.
   
this is describing retransmission without any conditions. A couple of sentences later, the text describes the conditions that trigger a retransmission, so the paragraph gets it right in total, but it might be clearer if this sentence said something like 

   Second, when a sender
   receives duplicate acknowledgments, or similar information via
   selective acknowledgments, the fast retransmit algorithm suspects data
   loss and can trigger a retransmission.
   
In this sentence,

   Further experimentation is needed to
   determine this and thereby move this specification from experimental
   to proposed standard.
   
if you make other text changes, you might consider s/to proposed standard/to the standards track/. In a perfect world, the specification might advance beyond proposed standard, given deployment experience ...
Alia Atlas Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Alvaro Retana Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Barry Leiba Former IESG member
No Objection
No Objection (2015-10-14 for -08) Unknown
A comment to Benoît's comment that quotes the opsdir review saying, 'I believe that it should be "provide" singular and not plural.'  No, "provides" goes with "algorithm", and is correct as written.
Ben Campbell Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Benoît Claise Former IESG member
No Objection
No Objection (2015-10-14 for -08) Unknown
Here is Tim's OPS DIR review:

This document describes an experimental modification to the TCP Retransmission Timeout (RTO) to act more aggressivly in connections that are short-lived or application limited.  It's well written.

The document is for both TCP and SCTCP, though primarily the TCP implementation is discussed. This is fine as it is experimental.

I found one thing in the introduction:

   This document describes a modified sender-side algorithm for managing
   the TCP and SCTP retransmission timers that provides faster loss
   recovery

I believe that it should be "provide" singular and not plural.

In section 4, there is this text:

   The RECOMMENDED value of rrthresh is four, as this value will ensure
   that RTOR is only used when fast retransmit cannot be triggered.
   This update needs TCP implementations to track the time elapsed since
   the transmission of the earliest outstanding segment (T_earliest).

The text is saying the implementation track time elapsed, so should it say:

"With this update, TCP implementations MUST track the time elapsed..."?
Deborah Brungard Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Jari Arkko Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Joel Jaeggli Former IESG member
No Objection
No Objection (2015-10-14 for -08) Unknown
tow Tim Wicinski performed the opsdir review.
Kathleen Moriarty Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Stephen Farrell Former IESG member
No Objection
No Objection (for -08) Unknown

                            
Terry Manderson Former IESG member
No Objection
No Objection (for -08) Unknown