Re: What can you use DSCP for?

["BELLEVILLE Ray" <Ray.Belleville () alcatel-lucent com>]

Triple play Solutions use DSCP all over the place. Lots of differenciated services, especially when subscriber 
management comes into play. Triple play is turning into 4 and 5xplay, then add the varying degrees of service and 
bundles available across the different services, and different requirements between the different data services (vodn 
internet, content storage, backup, sharing). Very useful tool.



----- Original Message -----
From: owner-nanog () merit edu <owner-nanog () merit edu>
To: John Kristoff <jtk () ultradns net>
Cc: nanog () merit edu <nanog () merit edu>
Sent: Tue Oct 30 07:04:52 2007
Subject: What can you use DSCP for?


On Mon, 29 Oct 2007, John Kristoff wrote:
> How much has really changed?  Do you (or if someone on these big nets
> wants to own up offlist) have pointers to indicate that deployment is
> significantly different now than they were a couple years ago?  Even
> better, perhaps someone can do a preso at a future meeting on their
> recent deployment experience?  I did one a couple years and I haven't
> heard of things improving markedly since then, but then I am still
> recovering from having drunk from that jug of kool-aid.  :-)

Once you get past the religious debates, DSCP can be very useful to
large, complicated networks with many entry and exit points.  Think
about how large networks use tools such as BGP Communities to manage
routing policies across many different types of interconnections. You
may want to consider how networks use similar tools such as DSCP to
mark packets entering networks from internal, external, source address 
validated, management, etc interfaces. There are limited code-points so
you can't be too clever, but even knowing on the other side of then
network that a packet entered the network through a spoofable/non-spoofable
network interface may be very useful.