RFC 4342, "Profile for Datagram Congestion Control Protocol (DCCP) Congestion Control ID 3: TCP-Friendly Rate Control (TFRC)", March 2006Source of RFC: dccp (tsv)
See Also: RFC 4342w/ inline errata
Errata ID: 830
Publication Format(s) : TEXT
Reported By: Eddie Kohler
Date Reported: 2007-02-07
Section 5 says:
The sender's measurement of the round-trip time uses the Elapsed Time and/or Timestamp Echo option contained in feedback packets, as described in Section 8.2. The Elapsed Time option is required, while the Timestamp Echo option is not. The sender maintains an average round-trip time heavily weighted on the most recent measurements.
It should say:
The sender's measurement of the round-trip time uses DCCP's mechanisms for round-trip time measurement. This includes Elapsed Time and/or Timestamp Echo options. As described in Section 8.2, feedback packets must carry an Elapsed Time option; Timestamp Echo is optional. The sender maintains an average round-trip time heavily weighted on the most recent measurements. Senders MAY use any available round-trip time measurements, including from the initial Request-Response packet exchange, to maintain this average. This differs from [RFC 3448], which constrains round-trip time measurements to feedback packets only.
Clarification of round-trip time measurement.
Reported By: Eddie Kohler and Sally Floyd, from Gerrit Renker and Arjuna Sathiaseelan