H3C MS4520V2-24TP, Руководство по настройке

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Configuring MCE
About MCE
The Multi-VPN Instance Customer Edge (MCE) feature allows multiple VPNs to share a CE with
ensured data security in an MPLS L3VPN network. MCE provides traffic separation between VPNs
by distinguishing routes of the VPNs.
MPLS L3VPN problems solved by MCE
MPLS L3VPN is a L3VPN technology used to interconnect geographically dispersed VPN sites.
MPLS L3VPN uses BGP to advertise VPN routes and uses MPLS to forward VPN packets over a
service provider backbone.
In conventional MPLS L3VPN, a VPN site must exclusively use a CE to connect a PE. With
increasing business, a private network must be divided into multiple VPNs and the VPNs must be
isolated from one another for data security. Using a CE exclusively for each VPN costs much in
buying and maintaining the network devices. Using a common CE for multiple VPNs cannot ensure
data security because the VPNs use the same routing table.
The MCE feature offers balance between cost and security. It creates multiple VPN instances on a
CE to provide logically separated routing tables and address spaces for the VPNs, so the VPNs can
share the CE. This CE is called the MCE device.
Basic MPLS L3VPN architecture
A basic MPLS L3VPN architecture has the following types of devices:
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Customer edge device —A CE device resides on a customer network and has one or more
interfaces directly connected to a service provider network. It does not support MPLS.
•
Provider edge device —A PE device resides at the edge of a service provider network and is
connected to one or more CEs. All MPLS VPN services are processed on PEs.
•
Provider device —A P device is a core device on a service provider network. It is not directly
connected to any CEs. A P device has only basic MPLS forwarding capability and does not
handle VPN routing information.