Re: mpls doubts

> 1) what is ment by ldp - igp synchornisation . ? by default its disabled
> ....what benifits i will get if i enable it ?

I think it may be beneficial for you to take a look at this document here:
http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/fsldpsyn.html

If you have any doubts left after that, let's follow it up here.

> 2) in the follwoing output outgoing actiion is Aggregate ...what does it
> imply ? i have not done summarization any where ....

It's an Aggregate label. In almost all cases, it indicates an MPLS
VPN, but it doesn't have to be (in your case it is).

> 3) why is it required that two PE must use loopback interface for BGP
> sessions ? why it is required that these loopback must be /32 route ?

It isn't required. However, if you are not using Loopbacks for
peering, or you are not using /32 masks, you need to understand the
implications. Not using /32 Loopback mask is kind of an issue with
OSPF that you may need to address. If you're not using Loopbacks, you
can use whatever interface you like, except the downstream interface
to your PE peer. Take a look at this:
http://blog.ipexpert.com/2010/05/31/next-hop-in-mpls-vpns/

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Marko Milivojevic - CCIE #18427
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