IPv6 Provider Edge Multipath
IPv6 Provider Edge Multipath
Internal and external BGP multipath for IPv6 allows the IPv6 router to load balance between several paths
(for example, same neighboring autonomous system (AS) or sub-AS, or the same metric) to reach its destination.
The 6PE multipath feature uses multiprotocol internal BGP (MP-IBGP) to distribute IPv6 routes over the
MPLS IPv4 core network and to attach an MPLS label to each route.
When MP-IBGP multipath is enabled on the 6PE router, all labeled paths are installed in the forwarding table
with MPLS information (label stack) when MPLS information is available. This functionality enables 6PE
to perform load balancing.
OSPFv3 6VPE
The Open Shortest Path First version 3 (OSPFv3) IPv6 VPN Provider Edge (6VPE) feature adds VPN routing
and forwarding (VRF) and provider edge-to-customer edge(PE-CE) routing support to Cisco IOS XR OSPFv3
implementation. This feature allows:
• Multiple VRF support per OSPFv3 routing process
• OSPFV3 PE-CE extensions
Multiple VRF Support
OSPFv3 supports multiple VRFs in a single routing process that allows scaling to tens and hundreds of VRFs
without consuming too much route processor (RP) resources.
Multiple OSPFv3 processes can be configured on a single router. In large-scale VRF deployments, this allows
partition VRF processing across multiple RPs. It is also used to isolate default routing table or high impact
VRFs from the regular VRFs. It is recommended to use a single process for all the VRFs. If needed, a second
OSPFv3 process must be configured for IPv6 routing.
The maximum of four OSPFv3 processes are supported.
Note
OSPFv3 PE-CE Extensions
IPv6 protocol is being vastly deployed in today's customer networks. Service Providers (SPs) need to be able
to offer Virtual Private Network (VPN) services to their customers for supporting IPv6 protocol, in addition
to the already offered VPN services for IPv4 protocol.
In order to support IPv6, routing protocols require additional extensions for operating in the VPN environment.
Extensions to OSPFv3 are required in order for OSPFv3 to operate at the PE-CE links.
VRF Lite
VRF lite feature enables VRF deployment without BGP or MPLS based backbone. In VRF lite, the PE routers
are directly connected using VRF interfaces. For OSPFv3, the following needs to operate differently in the
VRF lite scenario, as opposed to the deployment with BGP or MPLS backbone:
Cisco IOS XR Virtual Private Network Configuration Guide for the Cisco CRS Router, Release 6.1.x
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Implementing IPv6 VPN Provider Edge Transport over MPLS