NAME

  ShutInCookieEchoed.seq - SHUTDOWN chunk is received in COOKIE-ECHOED State


PURPOSE

  To check that if a SHUTDOWN is received in the COOKIE-ECHOED state, the
  SHUTDOWN chunk SHOULD be silently discarded.


SYNOPSIS

  ./ShutInCookieEchoed.seq [-tooloption ...] -pkt ./ShutInCookieEchoed.def
    -tooloption : v6eval tool option
  See Also: ../common/STD_PKT_COMMON.def
            ../common/SCTP_COMMON.def


PRE-TEST CONDITION

  Association is not established between endpoint A and B. Arrange the
  data in endpoint A such that SHUTDOWN message is sent to endpoint B
  after receiving COOKIE-ECHO message from it.


TEST PROCEDURE

  Endpoint A                           Endpoint B                ULP
  (CLOSED)                             (CLOSED)
                                            <-------- Associate
                   <----------------    INIT
   INIT-ACK        ----------------->
                   <----------------    COOKIE-ECHO
                                          (Start T1-Cookie timer)
   SHUTDOWN        ----------------->   Discard SHUTDOWN message
                                          T1-Cookie timer expires
                   <----------------    COOKIE-ECHO
  TEST DESCRIPTION:
  1. Try to create an association between endpoint A and B by sending
     COOKIE-ECHO message. Send SHUTDOWN message from the other endpoint.
     Record the message sequence using an emulator. 
  2. Check A: SHUTDOWN message is silently discarded. 
  3. Check B: After expiry of T1-Cookie timer COOKIE-ECHO message is 
     transmitted again.


NOTE

  None


REFERENCE

  RFC 4960
  9.2.  Shutdown of an Association
    If a SHUTDOWN is received in the COOKIE-WAIT or COOKIE ECHOED state,
    the SHUTDOWN chunk SHOULD be silently discarded.
    If an endpoint is in the SHUTDOWN-SENT state and receives a SHUTDOWN
    chunk from its peer, the endpoint shall respond immediately with a
    SHUTDOWN ACK to its peer, and move into the SHUTDOWN-ACK-SENT state
    restarting its T2-shutdown timer.
    If an endpoint is in the SHUTDOWN-ACK-SENT state and receives a
    SHUTDOWN ACK, it shall stop the T2-shutdown timer, send a SHUTDOWN
    COMPLETE chunk to its peer, and remove all record of the association.