RFC 3124 (rfc3124) - Page 2 of 22

The Congestion Manager

RFC 3124                 The Congestion Manager                June 2001


   MACROFLOW

      A group of CM-enabled streams that all use the same congestion
      management and scheduling algorithms, and share congestion state
      information.  Currently, streams destined to different receivers
      belong to different macroflows.  Streams destined to the same
      receiver MAY belong to different macroflows.  When the Congestion
      Manager is in use, streams that experience identical congestion
      behavior and use the same congestion control algorithm SHOULD
      belong to the same macroflow.

   APPLICATION

      Any software module that uses the CM.  This includes user-level
      applications such as Web servers or audio/video servers, as well
      as in-kernel protocols such as TCP [Postel81] that use the CM for
      congestion control.

   WELL-BEHAVED APPLICATION

      An application that only transmits when allowed by the CM and
      accurately accounts for all data that it has sent to the receiver
      by informing the CM using the CM API.

   PATH MAXIMUM TRANSMISSION UNIT (PMTU)

      The size of the largest packet that the sender can transmit
      without it being fragmented en route to the receiver.  It includes
      the sizes of all headers and data except the IP header.

   CONGESTION WINDOW (cwnd)

      A CM state variable that modulates the amount of outstanding data
      between sender and receiver.

   OUTSTANDING WINDOW (ownd)

      The number of bytes that has been transmitted by the source, but
      not known to have been either received by the destination or lost
      in the network.

   INITIAL WINDOW (IW)

      The size of the sender's congestion window at the beginning of a
      macroflow.






Balakrishnan, et. al.       Standards Track