Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 

trust dscp

dear all,

What is the default behaviour on CRS nodes when it comes to incoming packets,  is packets marking trusted or maked down ?

I tested trusting via policy map, but option was not available to trust. Is there a similar command to IOS to explicitly trust dscp or cos ?

TIA

Samir

1 ACCEPTED SOLUTION

Accepted Solutions
Cisco Employee

Re: trust dscp

Hello Samir,

That should be CRS default behavior.

Transition               Behavior

==============================================================================

COS > L2VPN         .1p bits are copied into EXP

L2VPN > COS         No copy by default. Default value of 0 is imposed in .1p field

IP to MPLS          IP Precedence value copied to MPLS EXP

MPLS to IP          No copy down behavior

PHP                 EXP bit not copied to bottom label

You can follow “DiffServ Tunneling Modes for MPLS Networks” document for more details on DiffServ in MPLS implementation.  It is written for IOS, but the approach is the same.

http://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a008022ad7e.shtml

Regards,

/A

2 REPLIES
Cisco Employee

Re: trust dscp

Hello Samir,

That should be CRS default behavior.

Transition               Behavior

==============================================================================

COS > L2VPN         .1p bits are copied into EXP

L2VPN > COS         No copy by default. Default value of 0 is imposed in .1p field

IP to MPLS          IP Precedence value copied to MPLS EXP

MPLS to IP          No copy down behavior

PHP                 EXP bit not copied to bottom label

You can follow “DiffServ Tunneling Modes for MPLS Networks” document for more details on DiffServ in MPLS implementation.  It is written for IOS, but the approach is the same.

http://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a008022ad7e.shtml

Regards,

/A

trust dscp

Many thanks for the confirmation !

Samir

1168
Views
10
Helpful
2
Replies
CreatePlease to create content