More than ever, high availability is at the forefront of the service provider?s selection criteria for routing systems. It is a requirement that has become more critical due to the unprecedented growth of IP services and the increasing use of IP for mission-critical and even life-line services. With more critical applications on the network, the cost of downtime escalates.

The demand for high availability routing has been most pronounced at the network or service provider edge where thousands of connections are hosted and rerouting options around a failed piece of equipment may be limited. In some cases, the customer may have only one termination point.

A well planned network architecture and design is the starting point for achieving a high availability network. The goal is to establish the baseline network for delivering high-performance services at the lowest possible cost while assuring SLAs can be met at all times.

In general, to accomplish this, the network planner must design and engineer reliability and resiliency into every level of the network to maximize service availability and minimize the probability and impact of failures. This must be balanced against the high cost associated with over engineering the network to achieve a high level of availability.

At the network level, the capabilities of a high availability router can be extended to protect against end-to-end network failures in the access, provider edge, and core components of the network. This includes the physical links, IP service delivery connections, and the routers that comprise the end-to-end network topology.

By leveraging and combining advanced router high availability features, resiliency can be extended beyond the router and into the end-to-end network to ensure non-stop service availability in the presence of network level outages. With a non-high availability router the only options the network planner may have is to over-engineer the network with redundant nodes and links. This is extremely undesirable for obvious economic, scalability, complexity, and long-term migration reasons.

Alcatel-Lucent has been investing in and delivering high availability routing and signaling solutions for several years. This paper discusses the standard based high availability MPLS features available to service providers. It also describes how Alcatel-Lucent?s advanced high availability offering on its new-generation service router helps diminish vulnerability at the network or service provider edge and alleviate the effect of a lengthy outage on IP networks.