Panasonic NN46240-710 - Manual (Page 116)

4 MPLS L2VPN troubleshooting
Nortel Secure Router 8000 Series
_________ Troubleshooting - VPN
4.1.6 Kompella MPLS Layer 2 VPN
Overview
Kompella mode implements Layer 2 VPN in an end-to-end fashion and uses BGP to transport
Layer 2 information and VC labels.
Unlike Martini mode, Kompella MPLS Layer 2 VPN requires dividing the entire operator
network into many VPNs, and globally numbering CEs within these VPNs instead of
processing the connection between CEs directly.
Similar to BGP/MPLS VPN, Kompella mode also uses the VPN target to control the sending
and receiving of VPN routes. This adds more flexibility to networking.
To set up a connection between two CEs, you must specify a separate CE ID for both the local
CE and the remote CE on the PE.
The Kompella mode supports local connection and remote connection. The Kompella mode
supports the following two types of inter-AS Layer 2 VPN.
• Multihop mode: adopts BGP label routes.
• Multiprotocol - Exterior BGP (MP-EBGP) mode: stores the label block on the ASBR.
Label block
In Kompella mode a label block is used to distribute labels. Labels can be allocated for multiple
connections at a time.
You can specify a local CE range that shows the number of CEs to which a local CE can connect.
The system allocates one label block to this local CE at a time, with the block size equal to the
CE range. This mode allows users to distribute extra labels for VPNs. This causes a waste of
labels in a short term but reduces the workload of future VPN expansion.
4.1.7 MPLS Layer 2 VPN IP-interworking
Two CEs of the same Layer 2 VPN can use different Layer 2 media to access the SP. To allow
them to communicate, you must configure Layer 2 VPN IP-interworking.
Configuration notes vary with the Layer 2 medium through which the CE connects to the SP.
CQ NOTE
The PE mentioned in the following section refers to a local PE unless otherwise stated.
Ethernet and VLAN
An interface or subinterface of an Ethernet type supports IP-interworking encapsulation. Note
the following points:
• It is not required to assign an IP address for the Ethernet interface on PE. Even if an IP
address is assigned, no routes generate.
• After the encapsulation, the Ethernet interface of PE processes only Address Resolution
Protocol (ARP) packets and IP packets. Other types of packets are discarded.
• After receiving IP packets from CE, PE will not update dynamic MAC addresses.
• If you configure IP-interworking encapsulation on an ATM interface or subinterface, you
cannot configure this encapsulation on the VE interface that is associated with the
Permanent VC (PVC).
4-6 Nortel Networks Inc. Issue 5.3 (30 March2009)