Overview - Cisco ASR 5000 Series Administration Manual

BGP MPLS VPNs
ASR 5500 as a PE

Overview

In this scenario, the ASR 5500 functions as a PE router sitting at the edge of the MPLS core. See the figure
below.
Figure 21: ASR 5500 as a PE
The ASR 5500 eliminates the need for an ASBR or PE as shown in the first two scenarios. In this scenario,
two main requirements are introduced: IBGP functionality and MPLS label distribution protocols.
The ASR 5500 can be configured to add two labels:
• an outer label learned from LDP or RSVP-TE (RSVP-Traffic Engineering)
• an inner label learned from MP-iBGP
This solution supports traffic engineering and QoS initiated via the ASR 5500.
Sample Configuration
In this example, VRFs are configured on the ASR 5500 PE and pools are associated with VRFs. The ASR
5500 exchanges VPN routes with its IBGP peers (PE routers) and learns the MPLS paths to reach PEs via
ASR 5500 System Administration Guide, StarOS Release 21.4
ASR 5500 as a PE
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