RIP Metric of 16 — What Does debug ip rip Reveal? You enable debug ip rip and see network 172.16.10.0 being advertised to your router with metric 16. What does a RIP metric of 16 indicate for that route?

Introduction / Context:RIP uses hop count as its metric. The protocol defines a maximum of 15 hops; anything beyond that is considered unreachable to prevent routing loops from persisting indefinitely.

Given Data / Assumptions:

• Protocol is RIP (v1 or v2).
• Metric scale: 1–15 reachable, 16 = infinite (unreachable).
• debug ip rip shows incoming updates and their metrics.

Concept / Approach:A metric of 16 in RIP is the protocol’s representation of infinity. It marks a destination as unreachable, often used in route poisoning to explicitly withdraw a route. This avoids transient loops by ensuring all routers quickly treat the network as down until a valid advertisement appears.

Step-by-Step Solution:Observe metric 16 in debug output.Map 16 → “infinite” in RIP metric space.Interpret as an unreachable/poisoned route.Expect neighbors to remove or de-preference the route accordingly.

Verification / Alternative check:Check the routing table (show ip route). You should not see a usable path for 172.16.10.0 from that source; if present, it may be via another neighbor at a metric between 1 and 15.

Why Other Options Are Wrong:

• A: 16 hops is beyond RIP’s maximum; the route would be considered unreachable.
• B: Delay units are not used by RIP (that is an IGRP/EIGRP concept).
• D: “Messages per second” is unrelated to the metric.
• E: Summarization length is unrelated to a metric value of 16.

Common Pitfalls:Confusing RIP’s metric of 16 with a legitimate distance; it is a sentinel for infinity only in RIP.

Final Answer:The route is inaccessible.