[ns] Re: RED does not drop packets

[Wen Shushan <wenss@uestc.edu.cn>]

I have solve it by myself: it's not a bug of RED, but unanimity of RED and
DropTail. If you are interested in it, see
"Unanimity: RED and DropTail"


> Hi, ns-users,
> When I use ns for a RED simulation. I found I can't control the gateway's
> character through RED arguments. e.g.
> 
> Queue set limit_ 2	;#buffer size in pkts
> #or I use Queue/RED to set buffer size directly
> Queue/RED set limit_ 2
> Queue/RED set maxthresh_ 1
> Queue/RED set thresh_ 1
> Queue/RED set setbit_  false	;#should drop pkts rather than mark them
> 
> The simulating result was different from what I had expected; the gateway
> did not drop packets even when the TCP source transmits bursty 4 pkts to the
> gateway.
> 
> If I did not use RED and I define the queue as DropTail, then the gateway will
> drop packet just as expected.
> 
> Who can help me solve this problems?