Re: [ns] Question on wireless

[engp9075@nus.edu.sg]

Hi Diepchi T Tran,

    I had the same problem before.     I think it is a bug !
    I am not sure if it has been solved in current version.

   In my  version, ifqLen $opt(ifqlen) can not change the length of the queue.

   Actually, ns does not use ifqlen_ at all (see ns-lib.tcl) .
   The queue length is controled by  limit_.
    The easy way to make the buffer bigger is to set limit_ directly.
    For example, if you want to change the queue length to 1000,
    add below line at the beginning of your tcl script .
    Queue set limit_  1000

Diepchi T Tran wrote:

> Hi ns-users,
> I simulate a wired+wireless network including mobile-ip. I saw some packets
> dropped in my trace file and the reason for the dropping is no buffer space
> in IFQ. I changed the length of the ifq ( ifqlen option) to a number much
> bigger than 50 packets. But I saw no change in the trace file. Could please
> you show me how to make the buffer in IFQ bigger in order to avoid the
> dropping of the packets.
>
> Thank you very much,
> Cindy
> Diepchi Tran
> Phone (216) 433-8861
> Fax   (216) 433-8705