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Re: altq on what interface on a bridged setup



> At 11.55 08/11/2004, you wrote:
> > > [router]-->[ext_if]-->[inf_if]-->[LAN]
> > >                         bridge
> > >
> > > Should I only apply queueing on the ext_if?
> >
> >The problem is when datas are knocking at the door of a NIC, they're
> >already here, and it's too late to preserve bandwidth.
> >
> >So, it's better to use queueing on internal interface of your bridge for
> >ingoing datas (which are going to the LAN), even if your lan is certainly
> >faster than a Web connection.
>
> Hi all,
>
> if I have to shape ingoing AND outgoing datas on a trasparent bridge,
> is it ok to apply queueing to both interfaces, ignoring
> the FAQ raccomandation?
How that said Alexandre - when you have incoming data in your router that is
to late to queuing that trafic. But using altq with ecn for that trafic you
could slow down incoming stream , and in result you have good shaping for
bigger streams (eg. transfer from ftp server, downloading sth. from www) and
worser for small packets like ICMP-Ping
>From OpenBSD FAQ (about ECN) :
"Explicit Congestion Notification (ECN) works in conjunction with RED to
notify two hosts communicating over the network of any congestion along the
communication path. It does this by enabling RED to set a flag in the packet
header instead of dropping the packet. Assuming the sending host has support
for ECN, it can then read this flag and throttle back its network traffic
accordingly. "
Maybe somebody know how ECN work exactly?
Darek