[c-nsp] Please advice: Inter-AS VRF & Multicast Traffic Control (MPLS migration)

Ralf NoTe ralf_network at hotmail.com
Sat Feb 27 03:20:39 EST 2010

Hi all experts,

        Need advice from experts, currently I work for MPLS network migration,
 the customer have 2 existing MPLS network with different AS number serve for
different services.

Old AS (AS65002) has existing old PE, RR and VRF service (VRF more than 1000).
 New AS (AS65003) has existing PE, RR, VLL & VRF service (VRF & VLL more than 2000).

Customer want to expand coverage area of MPLS domain AS65003 by
 install new PE type which running IGP ISIS and BGP same with PE in MPLS AS65003
and replace existing old PE in MPLS AS65002. 

That means all of old VRF in old PE AS65002 must be migrated to new PE in AS65003.

All of new PE in MPLS AS65003 is ASBR (more than 100 routers), Each new PE have 2 links
 connect by dual homing point to differrent 2 of ASBR (old) PE in MPLS AS65002.

Currently multiple P in AS65002 act as RR with BGP cluster concept 
During or after migration, P/RR may be need to be migrated to P/PE/ASBR/RR by functionality.

Requirement from customer
1. Traffic for old VRF in AS65002 (but already migrate to new PE in AS65003) 
should via old MPLS core AS65002.
2. ASBR in both of MPLS network dont want to participated with routes all of VRFs in existing domain.
 (may be Inter-AS option C will meet the requirement right? please advice.)

3 type of VRF traffic in new PE MPLS AS65003

VRF type 1: 
Traffic AS 65003 -> 65002 (e.g. Internet service)
Traffic AS 65003 -> 65002 -> 65003 (e.g. peer to peer traffic in VRF internet service)

VRF type 2:
Traffic 65003 -> 65002 (in case of PE in different AS) 
Traffic 65003 -> 65002 -> 65003 (in case of PE in same AS65003) 
(e.g. old corporate VRF service in 65002)

VRF type 3:
Traffic 65003 -> 65003
(e.g. corparate VRF service in 65003)

What is the solution of Inter-AS provider should be apply for this scenario?

How to control VRF traffic for all of 3 type with different path between 2 MPLS network?
How to share load of traffic between new PE (ASBR) in MPLS AS65003
Inter-AS with 2 of ASBR (PE) in MPLS AS65002?

How to prevent BGP routing loop?

If all of old PE in MPLS AS65002 running global multicast with pim spase mode, SSM & anycast RP, 
After migrate to new PE, How about multicast traffic?

What is solution for multicast migration between different MPLS domain? 
Inter-domain by multicast BGP, MSDP, incongruent routing?

Technical advice for migration solution highly requires urgently!!!


Thank you for your kindly advice.
All of your suggesstion have benefit to me.


p.s. network diagram for you reference in the attachment.

Best Regard,



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