Dummynet and simulating random delay

[Bruce M. Simpson]

Luigi Rizzo wrote:
> On Wed, Jan 24, 2007 at 06:10:21PM +1100, Peter Jeremy wrote:
>   
>> On Tue, 2007-Jan-23 14:22:54 -0500, Andresen, Jason R. wrote:
>>     
>>> I have a project that requires me to simulate a link with varying but
>>> well defined delay.  The link is guarenteed to deliver packets in
>>> order, so I wish to maintain that behavior with Dummynet.
>>>       
>> I don't think dummynet can do this in its current form.  Based on
>>     
>
> actually dummynet never does reordering within a single pipe, even
> if you change the delay on the fly.
>
> But this said, you should explain "varying but well defined delay",
>   
Hitting up Google reveals someone hacked Dummynet to introduce per-flow 
randomness in a uniform distribution:
http://www.cs.unc.edu/~jeffay/dirt/FAQ/dummynet-modifications.html

However, they included entire source files against FreeBSD 4.5; 
forward-porting should hopefully not be too tedious for an interested party.

Regards,
BMS