[c-nsp] Define MPLS default EXP value?

[Patrick Abeldt]

Hi all,

we're planning to introduce MPLS within our network backbone, among other
things for QoS purposes. Our current concept is based solely on using EXP
values for different priority levels (the IP TOS fields need to be left
unchanged.)

Aside from applications which require higher-than-normal forwarding
priorities, we have a small number of traffic flows which we'd like to
assign a lower-than-normal priority. As far as I can see, this would
require an EXP value > 0 for standard traffic. More precisely, I'd need to
set a specific default EXP value for all labels imposed on a MPLS router,
regardless of interface etc. Are there easy methods to achieve this goal,
preferably on the global configuration level?

The only solution I've found so far is to impose that default EXP value
via a service policy attached to the respective interfaces. But given the
number of interface configs, this would be extremely cumbersome to manage,
and additionally it would interfere with existing service policies. I
think this is definitely not the way to go.

Any suggestions regarding an alternative design would be also welcome.
We're using c6500/Sup720/PFC3 devices with IOS version
s72033-advipservicesk9_wan-mz.122-33.SXI3.

Thanks for your advice,
Patrick