NAME

hostRecvRaReachableTime - Verifying that NUT recognize ReachableTime

TARGET

Host only

SYNOPSIS

  hostRecvRaReachableTime.seq [-tooloption ...] -p hostRecvRaReachableTime.def

INITIALIZATION

1. Set ReachableTime by router X.
2. Create the state of neighbor cache entry for TN.
3. Set its state to REACHABLE whose IsRouter flag is FALSE.

  TN                 NUT
  ----------------------
  State: NONCE (for all)


  ==== unsolicited RA ===>
       src=X's link-local
       dst=all-node
       M=0, O=0
       RouterLifetime=600
       ReachableTime=a test condition
       RetransTimer=0
       w/ SLLA


  State: NONE (for TN), STALE(for X)


  ==== echo-request ===>
       src=TN's link-local
       dst=NUT's link-local


  <=== multicast NS ====
       src=NUT's link-local
       dst=solicited-node[TN's link-local]
       w/ SLLA
       timeout=RETRANS_TIMER * MAX_MULTICAST_SOLICIT


  ==== solicited NA ===>
       src=TN's link-local
       dst=NUT's link-local
       R=0, S=1, O=1
       target=TN's link-local
       w/ TLLA


  State: REACHABLE (for TN), STALE (for X)

TEST PROCEDURE

hostRecvRaReachableTime verifies that NUT recognize ReachableTime.

  TN               NUT
  ----------------------
  State: REACHABLE (for TN)


  Wait for some seconds


  Judgment: Examining NUT's neighbor cache state



JUDGMENT


6.3.4.  Processing Received Router Advertisements


   If the received Reachable Time value is non-zero the host SHOULD set
   its BaseReachableTime variable to the received value.  If the new
   value differs from the previous value, the host SHOULD recompute a
   new random ReachableTime value.  ReachableTime is computed as a
   uniformly-distributed random value between MIN_RANDOM_FACTOR and
   MAX_RANDOM_FACTOR times the BaseReachableTime.  Using a random
   component eliminates the possibility Neighbor Unreachability
   Detection messages synchronize with each other.

  ==============+===================+==================
  RA received   | Wait Time
  by NUT        |
  --------------+-------------------+------------------
  ReachableTime | t <               | t >
                | ReachableTime *   | ReachableTime *
                | MIN_RANDOM_FACTOR | MAX_RANDOM_FACTOR
  ==============+===================+==================
  60            | t < 30, REACHABLE | t > 90,  STALE
  --------------+-------------------+------------------
  30            | t < 15, REACHABLE | t > 45,  STALE
  --------------+-------------------+------------------
  90            | t < 45, REACHABLE | t > 135, STALE
  ==============+===================+==================




TERMINATION

  1. Send RA with ReachableTime=30sec to set TN's reachable time
     to the default value.


  2. Send RA with RouterLifetime=0 to clear the Default Router List.



NOTE

  The test does not invoke any remote command.



SEE ALSO

  perldoc V6evalTool
  perldoc V6evalRemote