This is the index of the Class-of-Service profile applied to this static tunnel, determining how traffic entering it is prioritized and shaped relative to other traffic sharing the same physical links. An admin cross-references this index against the CoS profile table to confirm the correct priority treatment -- e.g. voice-grade low latency versus best-effort -- is actually applied to this specific tunnel rather than a default profile. For example, CoS profile index 3 assigned here might correspond to an expedited-forwarding profile, meaning this tunnel's traffic gets priority queuing ahead of tunnels using a lower-priority profile index.