[Ns-developers] AODV bug

[Tom Henderson]

Marco Fiore wrote:
> Hi all,
> 
> I found the following bug in ns-2.31 AODV implementation.
> In 
> the forward() function, all broadcast packets are delayed
> by a 
> uniformly distributed amount of time in [0,10]ms.
> I think this is to 
> introduce jitter in AODV-related broadcast
> messages.
> 
> However, this 
> also affects broadcasts from upper layers,
> which I find unmotivated and 
> even disruptive (as in the
> case of an application I'm coding).
> Thus, I 
> suggest that the following fix is introduced in the
> next release of the 
> code:
> 
> diff aodv_patched/aodv.cc aodv/aodv.cc
> 1036,1046c1036,1040
> <        // Added by Marco Fiore to avoid random jitter on non-AODV 
> broadcasts
> <        if(ch->ptype() == PT_AODV) {
> <      /*
> <       *  
> Jitter the sending of broadcast packets by 10ms
> <       */
> <      
> Scheduler::instance().schedule(target_, p,
> <                                          0.01 * Random::uniform());
> <    }
> <    else {
> <      Scheduler::instance().schedule(target_, p, 
> 0.);
> <        }
> ---
>>    /*
>>     *  Jitter the sending of broadcast 
> packets by 10ms
>>     */
>>    Scheduler::instance().schedule(target_, 
> p,
>>                                          0.01 * Random::
> uniform());
> 
> thanks,
> 
> Marco
> 
> 

Marco,
This seems reasonable; I'll run it by the people who most recently were 
maintaining AODV and if no problems or other list feedback, we can add 
this to the next release.

Tom