Diable PHP on MPLS

[arun kumar]

Hi

Is it possible to disable PerHopBehavior in MPLS network. If so are there any specific reason/advantages of doing that.

Thanks

[Harold Ritter]

Are you asking about disabling penultimate hop popping (PHP) as per the title of your posting or disabling per hop behavior (PHB)?

Here's a document discussing the different tunneling modes in an MPLS network.

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

Regards,

[arun kumar]

Hi Harold,

Sorry it was a typo error.. i meant of disabling Penultimate Hop Popping... not Per Hop Behavior...

[attrgautam]

I think the default behaviour is to have penultimate hop popping but if you still want a label to be tagged on the last hop, the ideal thing to do would be to advertise an explicit Null to the router. This way, there is a label on the last hop though the label value is always 0

[etienne.basset]

hello

yes by default a router advertise an 'implicit null' label for directly connected routes to his neighbors (label 3 afaik).

You can send an 'explicit null' label with value 0 with the global command 'mpls ldp explicit-null [for acl] [to acl]'

regards

etienne