LARTC - May 2001 - Forcing delay and setting bucket size

Hello all,
First I''ll state my final goal - In case someone knows an existing
piece of
code that does the trick: To use Linux with two network interfaces as a
router and link simulator with the following features: 
1. Limited bandwidth 
2. Specified propagation delay which affects each packet going out of an
interface
3. Limited bucket size (send buffer) for each interface.

I know how to do no. 1 using CBQ. What about 2 and 3 ? I haven''t seen
any
qdisc that deliberately imposes a specified delay. How can the send buffer
size be changed ? I can see its current value in the
''ifconfig'' output,
under ''txqueuelen'', but I don''t know how to modify
it.

Best Regards

Oded Shaham
Flash Networks
16 Galgalei Haplada, Herzliya, Israel
Tel: +972-9-9580666 ext. 215
Fax: +972-9-9564888
Cell phone: +972-5-4552009 
Email: oded@flashnetworks.com

> Hello all,
> First I''ll state my final goal - In case someone knows an existing
piece
of
> code that does the trick: To use Linux with two network interfaces as a
> router and link simulator with the following features:
> 1. Limited bandwidth
> 2. Specified propagation delay which affects each packet going out of an
> interface
> 3. Limited bucket size (send buffer) for each interface.
>
> I know how to do no. 1 using CBQ. What about 2 and 3 ? I haven''t
seen any
> qdisc that deliberately imposes a specified delay. How can the send buffer
> size be changed ? I can see its current value in the
''ifconfig'' output,
> under ''txqueuelen'', but I don''t know how to
modify it.
you can try the iptables function....
but your kernel have to update to 2.4