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L2 redundancy for MPLS Layer2 Access network

Please find the attachment for the network diagram. MSAN is connected to the layer 2 access switch SW3. SW3 has two uplinks, one goes to SW1 and other goes to SW2. SW1 has the uplink to one of the PE and SW2 has the uplink to other PE. MSAN provides Internet, Voice and IPTV. Internet is using PPPoE. So there is an l2 tunnel from MSAN to BRAS which is connected to the MPLS. MSAN will use only one vlan for all the access PVCs. Voice is provided using L3 vpn. MSAN should access the VOICE VPN via both PE routers. IPTV is using multcast. PIM is configured till PE routers. Requirment is as follows,

1)Failure of links between switches and routers should not affect any services.

2) Failure of switches or routers should not affect the any services.

What is the solution to acchive the requirments?



We need to have redundant PPPOE connection via both PE routers.

Hall of Fame Super Silver

Re: L2 redundancy for MPLS Layer2 Access network

Hello Senthil,

as far as I've understood your post.

services: one L2 Vlan for each service that will be defined on SW1 - SW3 and allowed on all inter-switch and switch-to-PE links all configured as L2 trunks.

Vlan 10: VoiIP over L3 VPN

Vlan 20: internet access PPPoE over EoMPLS pseudowire

Vlan 30: another L3 VPN for multicast

2) Fault-tolerance

SW3 and the BRAS are single points of failure you cannot be fault tolerant at level 1 (every possible single link failure, every possible single device failure) with this architecture.

Hope to help


New Member

Re: L2 redundancy for MPLS Layer2 Access network

Hi Giuseppe,

Thanks for your reply.

SW3 will be a stack switch. Multicast will be in global routing table. Our aim is to give fault tolerance at access level.