H3C S9500 Series Operation Manual page 899

Operation Manual – MPLS L3VPN
H3C S9500 Series Routing Switches
1.1.1 MPLS L3VPN Model
I. MPLS L3VPN model
Figure 1-1 MPLS L3VPN model
As shown in
CE (Customer Edge) device: It is a composing part of the customer network, which
is usually connected with the service provider directly through an interface. It may
be a router or a switch which cannot sense the existence of VPN.
PE (Provider Edge) device: It is an edge device of the provider network,
connecting with CE devices directly. In MPLS network, a PE device processes all
the operations for VPN. PE needs to possess MPLS basic forwarding capability.
P (Provider) device: It is the backbone router in the provider network, which is not
connected with CE directly. P router needs to possess MPLS basic forwarding
capability.
The classification of CE and PE mainly depends on the range for the management of
the provider and the customer, and CE and PE are the edges of the management
ranges.
II. Nested MPLS L3VPN model
In a basic MPLS L3VPN model, the PEs are in the network of the service provider and
are managed by the service provider.
When a VPN user wants to subdivide the VPN into multiple VPNs, the traditional
solution is to configure these VPNs directly on the PEs of the service provider. This
solution is easy to implement, but has the following disadvantages: the number of the
VPNs carried on PEs may increase rapidly; the operator may have to perform more
Figure 1-1, MPLS L3VPN model contains three parts: CE, PE and P.
Chapter 1 MPLS L3VPN Configuration
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