[c-nsp] No DSCP transparency, please

[Saku Ytti]

On (2006-07-20 20:17 +0200), Asbjorn Hojmark - Lists wrote:

> (I know you can re-mark and/or classify on the egress interface,
> based on EXP bits, but even that is implemented really ugly).

I have issue that's bit touching the issue you're having. 
In many cisco platforms you can 'copy' MPLS EXP to 'qos-class'
and then use 'qos-class' in IP egress interface, effectively
to do QoS based on the MPLS EXP value as it was when MPLS
packet came in to the PE, instead of the ToS value in packet,
what ever it might be.
In 7600 LAN cards this unfortunately doesn't appear to be
supported today. But I suspect that technically it might
be possible, if you could configure the internal DSCP value
manually using service-policies, so you'd use the internal
DSCP value just the same way you can use 'qos-class'. 
I wonder if the hardware could support setting and matching 
internal DSCP value in MQC?

I know that eg. MPLS EXP imposition is done like, in IP
ingress MPLS EXP imposition only sets the internal DSCP
value, and then on MPLS egress internal DSCP value is copied
as MPLS EXP value.

-- 
  ++ytti