Technical Summary
This note describes an optional modification for TCP's slow-start for use
with TCP connections with large congestion windows. For TCP connections tha
are able to use congestion windows of thousands (or tens of thousands) of
MSS-sized segments (for MSS the sender's MAXIMUM SEGMENT SIZE), the current
slow-start procedure can result in increasing the congestion window by
thousands of segments in a single round-trip time. Such an increase can
easily result in thousands of packets being dropped in one round-trip time.
This is often counter-productive for the TCP flow itself, and is also hard o
the rest of the traffic sharing the congested link. This note describes
Limited Slow-Start as an optional mechanism for limiting the number of
segments by which the congestion window is increased for one window of data
during slow-start, in order to improve performance for TCP connections with
large congestion windows.
This document also compares the proposed approach with alternative solutions
Working Group Summary
Many solutions have been considered for addressing the known issues with TCP
performance in a context of high congestion window sizes; this document form
a part of a larger HighSpeed TCP proposal. The community TSVWG welcomed the
opportunity to further explore this Experimental mechanism, and supported th
advancement of this document.
Protocol Quality
This document was reviewed for the IESG by Jon Peterson.