Re: [ns] problems running wireless cum wired example

[Tom Henderson <tomh@tomh.org>]

This error message can occur in mixed wired/wireless simulations 
for the following reason: 
it may be the case that, at some point during the evolution
of your topology, some nodes are disconnected.  Let's
suppose that you have 17 nodes (numbered 0 through 16)
and you are sending packets to node 16.  Now lets say
that node 16 is disconnected.  The routes may
be recomputed, but now since there is no node in
the connected topology connected to node 16, there
will be no dynamic increase of the route_ table size
beyond 16 entries (because "route_" is destroyed and
created anew upon routing table reset, and incremented by
a factor of two whenever needed during the insert() method). 
Hence, when you call lookup_flat() to find a route to node 16, 
the test fails due  to "node out of range". But the 
simulation may still run fine.

The reason that this would not happen in normal wireless
simulations is that the OTcl routing code is not ever
used.

Tom


On Sat, 3 Nov 2001, divyank shukla wrote:

> hi all
>      I ran the wired-cum-wireless*.tcl in the
> directory ~/tcl/ex and the message i got was node out
> off reach is this a persistent problem or we need some
> patch to make the scenario work i need to understand
> this before i make any contribution thanks
> in advance
>                         divyank