MF52348 - TCPIP-OTHER-INCORROUT IDS ACKSTORM EVENT GENERATED BY TCP/IP

TYPE PROGRAM  REL  NUMBER   MIN/MAX  OPTION
---- -------- ---  -------  -------  ------
CO   5770999  710  MF49821   00/00    0000



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APAR Error Description / Circumvention

-----------------------------------------------
Intrusion Detection System Generates ACKSTORM Event Because of
TCP/IP Window Probes

CORRECTION FOR APAR MA40530 :
-----------------------------
A non-standard window probe was received and this caused TCP to
trigger its notification to IDS of a possible ACKSTORM. The test
for a possible ACKSTORM will be relaxed so that this type of
window probe, which is used by some systems, does not needlessly
trigger this event.

CIRCUMVENTION FOR APAR MA40530 :
--------------------------------
None.


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Supersedes

PTF/FIX NO(S).  APAR TITLE LINE
--------------  ------------------------------------------------------------
   MF48598      LIC-COMM-TCPIP Transport Fixes
   MF50394      LIC-COMM-TCPIP-UNPRED RETRANSMISSION TIMER HIGH
   MF49877      LIC-COMM-TCPIP TCP Buffer Copy Prevention

Summary Information

System i Support