questions about errormodel

[Arnaud Legout <Arnaud.Legout@eurecom.fr>]

Hi, 
I want to generate deterministic losses like : 'I loss n packets every
m packets'.
My simple example is :

n1-----n2----n3    
n1 : tcp sender
n3 : tcp sink
n2 : the node that experiences losses

ns documentation talks about errormodel with probabilistic losses. I see
in tcl/test/topologies.tcl this example that seems to not use random
variable but
I don't understand all the parameters :

    set lossylink_ [$ns link $node_(r1) $node_(k1)]
    set em [new ErrorModule Fid]
    set errmodel [new ErrorModel/Periodic]
    $errmodel unit pkt
    $errmodel set offset_ 1.0
    $errmodel set period_ 25.0
    $lossylink_ errormodule $em
    $em insert $errmodel
    $em bind $errmodel 0

thanks for any help

Arnaud. 


-- 
----------------------------------------------------------------------
Arnaud Legout

Institut Eurecom               	Phone : 00.33.4.93.00.26.61
2229, route des Cretes         	Fax   : 00.33.4.93.00.26.27
BP 193                         	E-mail: Arnaud.Legout@eurecom.fr
06904 Sophia Antipolis cedex    Web   : http://www.eurecom.fr/~legout    
FRANCE                    
----------------------------------------------------------------------