• Ilpo Järvinen's avatar
    [TCP]: SACK enhanced FRTO · 4dc2665e
    Ilpo Järvinen authored
    Implements the SACK-enhanced FRTO given in RFC4138 using the
    variant given in Appendix B.
    
    RFC4138, Appendix B:
      "This means that in order to declare timeout spurious, the TCP
       sender must receive an acknowledgment for non-retransmitted
       segment between SND.UNA and RecoveryPoint in algorithm step 3.
       RecoveryPoint is defined in conservative SACK-recovery
       algorithm [RFC3517]"
    
    The basic version of the FRTO algorithm can still be used also
    when SACK is enabled. To enabled SACK-enhanced version, tcp_frto
    sysctl is set to 2.
    Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    4dc2665e
tcp_input.c 138 KB