[ns] One question about DV routing.

[Zhi Li <lizhi@cse.msu.edu>]

Hi,
I have the following partial of simulation code.
I dumped the routing table information twice at different time.
It is so strange that the routing tables are very different:
First time:
        0       1       2       3       4
0       --      2       2       2       2
1       2       --      2       2       2
2       0       1       --      3       4
3       2       2       2       --      4
4       2       2       2       3       --

Second time:
       0       1       2       3       4
0       --      2
1       --      2
2       0       1       --      3       4
3       2       --      4
4       2       3       --

I am very anxious to know  the reason. Could you please
tell me?
Thank you very much!

Best,
Zhi Li


#               $n0       $n3
#                  \     /   \
#                   \   /     \
#                    $n2-------$n4
#                   /
#                  /
#               $n1
#
set ns [new Simulator -multicast on]
$ns duplex-link $n(0) $n(2) 10Mb 2ms DropTail
$ns duplex-link $n(1) $n(2) 10Mb 2ms DropTail
$ns duplex-link $n(2) $n(3) 5Mb 10ms DropTail
$ns duplex-link $n(3) $n(4) 5Mb 10ms DropTail
$ns duplex-link $n(2) $n(4) 2Mb 10ms DropTail
$ns rtproto DV
$ns compute-routes
$ns dump-routelogic-nh
$ns at 1.9 "$ns dump-routelogic-nh"