Let me take a stab at answering my own question.  Let me know if i am
correct


#1.   Technically this is not need because R1 is receiving loopback routes
for the other routers from R2 and R8.   So all we need is to get the BGP
routes between R2 and R8.  R2 and R8 already know how to get to each others
loopback via R1.  So as long as we peer R2 to R8 using loopbacks we are good
to go.

#2.   IF R1 was only accepting R2 and R8 loop backs and had no idea how to
get to the loopbacks of the other routers we can use the 'send-label' which
turns on mpls switching on the interface facing the peer for which it was
enabled.  Since R8 and R2 now know about the mpls lables for all loopbacks
they it insert the shim header with the label to get to R8 or R2 depending
on the direction of travel.  R1 has labels for these and switches the packet
to the correct Router.  This is eliminating the need for R1 to have an ipv4
route for the other routers loopbacks

I think the keep point i was missing is that the 'send-label'  command
actually turns  on mpls switching on the interface facing the peer

if i am incorrect in my understanding please let me know

Aaron





On Thu, Aug 4, 2011 at 10:49 AM, Aaron Moreck <[email protected]> wrote:

> On ticket #2  it says our networks are being blackholed in AS1.
>
> ----------------------------------------------------------------------------------------------
>
> The question leads us to MPLS lables using the 'send-label'  on the
> neighbor sessiosn to AS1
>
> I solved the ticket WITHOUT using 'send-labels'  but DID peer AS78 to AS24
> using loopbacks, ebgp multi-hop, and filtering out R2 and R8 loop backs on
> this session.
>
> I had full connectivity for Loopbacks and didnt need to 'send-labels' to
> AS1
>
> The DSG did the BGP peering R2 - R8 the same as I did how ever they also
> used 'send-label'
>
>
> My questons
>
> #1  why is the 'send-label' included in DSG?
>
> #2 Second question and probably more important is i am really struggling
> with MPLS labels using the send-label via BGP and not using LDP or TDP
> between peers.   I dont understand how this works on a fundamental level.
> Can someone give me a specific example of this in action?
>
> Aaron
>
>
>
>
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