LARTC - Apr 2005 - IMQ: why do I need IMQ ?

Hello there,

Can someone please explain why do one neeed IMQ ?

I can already shape incoming traffic on my nat router by creating
qdiscs on LAN-side interface. I have done some tests, whith simple
bandwidth limmiting, and it works.

I''ve read just about all the stuff on www.linuximq.net ... but
couldn''t make myself an ideea on why would someone need IMQ for
ingress policing ...

Thanks in advance.

Have a nice day.




-- 


Radu Cugut

mobile: +40 742 045686
web:    http://rcugut.has.it

On Sun, Apr 10, 2005 at 07:14:22PM +0300, Radu CUGUT
wrote:
> Hello there,
hi
> Can someone please explain why do one neeed IMQ ?
- if you want to shape incoming traffic
- if you want to bundle devices
> I can already shape incoming traffic on my nat router by creating qdiscs on
> LAN-side interface. I have done some tests, whith simple bandwidth
> limmiting, and it works.
It doesn''t manage traffic caused by the router itself. If you can avoid
this
though, you''re right, just make sure you filter router''s
traffic on the LAN
side too.

Even a router without much functionality often provides DNS proxy, ssh or
http(s) access, which is already its own traffic and IMQ helps in that case.
> I''ve read just about all the stuff on www.linuximq.net ... but
couldn''t make
> myself an ideea on why would someone need IMQ for ingress policing ...
Because shaping is more than policing ;-)
> Radu Cugut
Bye,

Peter Surda (Shurdeek) <shurdeek@routehat.org>, ICQ 10236103,
+436505122023

-- 
                    "Where do you want to go to die?"

In the case where you have a router (that is not generating signficant 
traffic itself) with one internet facing interface and one LAN facing 
interface, you really don''t need IMQ.

It becomes very useful in alternate cases where, for example, you have 
multiple interfaces facing the internet (eg, two DSL connections).  In this 
case the data coming into one of the internet facing interfaces no longer 
equals the amount of data exiting the LAN facing interface, so trying to 
control the internet ingress by policing the LAN egress is no longer a 
simple matter.

But yea, in the simple firewall/shaping router case, IMQ is generally not 
worth the time.  Add multiple interfaces coming in our out, or add VPN to 
the ruoter, and it becomes a more complicated situation.

----- Original Message ----- 
From: "Radu CUGUT" <rcugut@gmail.com>
To: <lartc@mailman.ds9a.nl>
Sent: Sunday, April 10, 2005 11:14 AM
Subject: [LARTC] IMQ: why do I need IMQ ?

> Hello there,
>
> Can someone please explain why do one neeed IMQ ?
>
> I can already shape incoming traffic on my nat router by creating
> qdiscs on LAN-side interface. I have done some tests, whith simple
> bandwidth limmiting, and it works.
>
> I''ve read just about all the stuff on www.linuximq.net ... but
> couldn''t make myself an ideea on why would someone need IMQ for
> ingress policing ...
>
> Thanks in advance.
>
> Have a nice day.
>
>
>
>
> -- 
>
>
> Radu Cugut
>
> mobile: +40 742 045686
> web:    http://rcugut.has.it
> _______________________________________________
> LARTC mailing list
> LARTC@mailman.ds9a.nl
> http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
>

OK, i''ve got the ideea. 
In conclusion if i have a simple:

LAN --- router --- WAN

i don''t need IMQ stuff :)

thanks

bye




-- 


Radu Cugut

mobile: +40 742 045686
web:    http://rcugut.has.it