Re: QoS for ADSL customers

[Sean Donelan <sean () donelan com>]

On Tue, 29 Nov 2005, Kim Onnel wrote:
> The links are now almost always fully utilized, we want to do some QoS to
> cap our ADSL downstream, to give room for the Corp. customers traffic to
> flow without pain.

While some people will cry network neutrality and think the Yellow Pages
must sell only one size listing, some people are willing to pay for
differentiated service.  Trying to classify "bad" traffic can be
done using products like Sandvine.  But it may be easier to classify "premium"
traffic and mark it for special handling, and then treating everything
that isn't marked as premium traffic as best effort traffic.

But expect great wailing and gnashing of teeth over setting or changing
DSCP/TOS bits or creating different queues for different traffic.  Should
DSCP bits in IP headers be treated like TTL bits which are modified by
the network.  Should ISPs use anti-spoofing techniques similar to prevent
the use of arbitrary IP addresses to control DSCP/TOS values in packet
headers?

Most routers already give priority to some types of traffic, such as
routing update packets.