Re: packet transfer across multiple LAN's in ns-2.1b5

[Yuri Pryadkin <yuri@who.isi.edu>]

Guru,

I've found the bug that was causing the problem you noticed.

Basically, as the packet was going up the stack of the first LAN,
hdr_cmn::direction_ was set to "up".  This value wasn't reset
afterwards, so when the packet was sent down the stack of the second
LAN, LL layer saw that direction_ was "up" and sent it back up thus
causing an infinite loop.  I added a one-liner fix to net-interface.cc
that resets this value when the packet leaves the network stack.

Please upgrade your net-interface.cc file from
http://www-mash.cs.berkeley.edu/cgi-bin/cvsweb/ns-2/net-interface.cc?rev=1.10

  -Yuri


Guruprasad Bhaskar <bguru@utdallas.edu> writes:
> 
> Hi folks,
> 
> I hope you got my previous message. I am herewith attaching the tcl script
> (to be compiled in ns-2.1b5) which simulates the scenario of 2 individual
> lans connected by an
> intermediate node. It initiates a TCP session between two nodes 1 
> and 4 each belonging to a different LAN. As you can see in the nam output,
> as soon as the TCP session starts, the packet transfer takes place only
> between nodes 3 and 4 which belong to the second LAN, and not between 1
> and 4 as defined in the script.
> 
> Could you please take a look at the nam output and see if this bug can be
> fixed,
> 
> Thanx a lot,
> Guru.