Design Lessons

A number of observations can be made from EuropCom design decisions:

• When mapped onto existing IPv4 IA and VPNv4 MPLS services, 6PE and 6VPE, respectively, offer a low-cost, low-risk deployment strategy. Reusing the existing LSPs further minimizes operating costs: Anything in the core that is already set up for existing LSPs (label distribution, FRR, and so on) will benefit IPv6, too.

• Link-local peering for eBGP PE-CE session is a useful and safe approach that simplifies the addressing planeven though it does not save the need to configure at least one global address in each box for network error reporting and network management.

• RR design for IPv6 is strictly identical in nature to the IPv4 RR design. Separating IPv4 RRs and IPv6 RRs is not required, but minimizes deployment risks.

• Whichever QoS mechanism is implemented in the core, and on the edges, it is far easier if it does not differentiate between IPv4 and IPv6. QoS MQC commands such as match precedence are useful because they apply to both protocols.

• A consistent MTU configuration that pushes PMTU management responsibility to the edges is a must for IPv6 deployment, unless P-routers are ICMPv6 capable.