Computing Backup Paths for LSPs Using Fate Sharing
Fate sharing allows you to create a database of information that CSPF uses to compute one or more backup paths to use in case the primary path becomes unstable. The database describes the relationships between elements of the network, such as routers and links. You can specify one or more elements within a group.
Through fate sharing, you can configure backup paths that minimize the number of shared links and fiber paths with the primary paths as much as possible, to ensure that if a fiber is cut, the minimum amount of data is lost and a path still exists to the destination.
For a backup path to work optimally, it must not share links or physical fiber paths with the primary path, ensuring that a single point of failure will not affect the primary and backup paths simultaneously.