Value,Description,Reference
0,"Shortest Path First (SPF) algorithm based on link metric.  This
        is the standard shortest path algorithm as computed by the IGP
        protocol.  Consistent with the deployed practice for link-state
        protocols, Algorithm 0 permits any node to overwrite the SPF path
        with a different path based on its local policy.",[RFC8665]
1,"Strict Shortest Path First (SPF) algorithm based on link
        metric.  The algorithm is identical to Algorithm 0 but Algorithm 1
        requires that all nodes along the path will honor the SPF routing
        decision.  Local policy at the node claiming support for Algorithm
        1 MUST NOT alter the SPF paths computed by Algorithm 1.",[RFC8665]
2-127,Unassigned,
128-255,Flexible Algorithms,"[RFC9350, Section 4]"