Very Computer

Quote:> Hi
> I am trying to se the result of delay in a small network. I have therefore
> made two client-server program to send data from client to the server. One
> of them using TCP socket and the other using UDP socket (In Unix platform ).
> I want to ask
>     -How could I add some delay in between each IP package going to the
> server ?
> Hope some body could help.

One such tool is available in FreeBSD, it's called DUMMYNET.

Manpage first line follows :
DUMMYNET(4)            FreeBSD Kernel Interfaces Manual            DUMMYNET(4)

NAME
     dummynet - Flexible bandwidth manager and delay emulator

SYNOPSIS
     #include <sys/types.h>
     #include <sys/queue.h>
     #include <netinet/in.h>
     #include <netinet/ip_fw.h>

     int
     setsockopt(raw_socket, IPPROTO_IP, ipfw option, struct ipfw, size)

DESCRIPTION
     dummynet is a system facility that permits the control of traffic going
     through the various network interfaces, by applying bandwidth and queue
     size limitations, and simulating delays and losses.

     In its current implementation, packet selection is done with the ipfw
     program, by means of ``pipe'' rules.  A dummynet pipe is characterized by
     a bandwidth, delay, queue size, and loss rate, which can be configured
     with the ipfw program. Pipes are numbered from 1 to 65534, and packets
     can be passed through multiple pipes depending on the ipfw configuration.

     Dummynet operates at the ip level, but if bridging extensions are en-
     abled, it is possible to pass bridged packets through pipes as well.

Quote:> Thanks  Loui