Ccc Mpls L2Vpn; Svc Mpls L2Vpn; Martini Mpls L2Vpn - 3Com MSR 50 Series Configuration Manual

1428 C 78: MPLS L2VPN C
HAPTER

CCC MPLS L2VPN

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SVC MPLS L2VPN

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Martini MPLS L2VPN

ONFIGURATION
The Kompella draft defines a CE-to-CE mode for implementing MPLS L2VPN on
the MPLS network. It uses extended BGP as the signaling protocol to advertise
Layer 2 reachability information and VC labels.
In addition, MPLS L2VPN can also be implemented by configuring VC labels
statically. CCC and SVC are two of the static implementation methods.
The following sections describe the characteristics of these implementation
methods for MPLS L2VPN.
Unlike common MPLS L2VPN, circuit cross connect (CCC) employs just one level of
label to transfer user data. Therefore, it uses label switched paths (LSPs) exclusively.
That is, a CCC LSP can be used to transfer only the data of the CCC connection; it
can neither be used for other MPLS L2VPN connections, nor for MPLS L3VPN, nor
for common IP packets.
The most significant advantage of this method is that no label signaling is required
for transferring Layer 2 VPN information. As long as MPLS forwarding is supported
and service provider networks are interconnected, this method works perfectly. In
addition, since LSPs are dedicated, this method supports QoS services.
There are two types of CCC connections:
Local connection: A local connection is established between two local CEs that
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are connected to the same PE. The PE functions like a Layer 2 switch and can
directly switch packets between the CEs without any static LSP.
Remote connection: A remote connection is established between a local CE
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and a remote CE, which are connected to different PEs. In this case, a static LSP
is required to transport packets from one PE to another.
You must configure for each remote CCC connection two LSPs, one for inbound
and the other for outbound, on the P device along the remote connection.
Static virtual circuit (SVC) also implements MPLS L2VPN by static configuration. It
transfers L2VPN information without using any signaling protocol.
The SVC method resembles the Martini method closely but does not use LDP to
transfer Layer 2 VC and link information. You only need to configure VC label
information.
The labels for CCC and SVC range from 16 to 1023, which are reserved for static
LSPs.
The key of the Martini method is to set up VCs between CEs.
Martini MPLS L2VPN employs VC type and VC ID to identify a VC. The VC type
indicates the encapsulation type of the VC, which can be ATM, VLAN, or PPP. The
VC ID uniquely identifies the VC among the VCs of the same VC type on a PE.
The PEs connecting the two CEs of a VC exchange VC labels through LDP, and
bind their respective CE by the VC ID.