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Routing & Switching · Advanced

Prefix SID

A global segment associated with an IGP prefix that steers traffic along the ECMP-aware shortest path to that prefix.

Definition

A node SID is a prefix SID on a router's loopback identifying that node. Anycast SIDs are prefix SIDs shared by several routers for redundancy.

Example

Label 16005 means 'reach R5 via shortest path'.

Exam tip

Prefix SID index must be unique per prefix in the domain.

Related terms