Cell Relay Archive

[Paul Koning <pkoning@xedia.com>]

Torsten wrote:
> 
> Hi,
> 
> with nrt-VBR it is allowed for the endsystem to premark cells as CLP=0
> or CLP=1,
> which could be used e.g. for layered video.
> But normally todays applications work with IP and possibly in the core
> network
> ATM is used.
> 
> How can an application premark packets in the IP world, so that the
> information
> about the marking condition is conveyed to the ATM cells of VBR?
> Is there any standardized method?

I don't know of a standardized method.

The approaches used for diff-serv marking could be applied.
For example, we build a router that does class-based queueing (CBQ),
which means it has a substantial amount of packet classification
capabilities.  Apart from making scheduling decisions, it can also
do diff-serv tagging based on that classification.  And if your
traffic is going out ATM, it can choose among several VCs and/or
control the CLP bit based on the classification.

All this is a local matter so it isn't actually a subject for
standardization.

	paul