RIP Behavior — Receiving a Higher-Cost Path for an Existing Network Two directly connected routers run RIP. If a router receives an update that advertises a higher-cost (larger hop count) path to a destination that already exists in its routing table with a lower cost, what does RIP do?

Introduction / Context:RIP chooses routes based on minimum hop count. When multiple advertisements for the same prefix arrive, RIP keeps the lowest-hop path. Understanding how RIP treats worse paths helps explain stable behavior and reduces unnecessary churn.

Given Data / Assumptions:

• RIP metric is hop count (lower is better).
• An existing route with lower hop count already resides in the RIB.
• A new update arrives with higher hop count.

Concept / Approach:RIP installs the best path by hop count. If a newly received advertisement has a worse metric, the router ignores it for route selection. Only if the existing route becomes invalid (for example, times out) or a strictly better metric is learned will the RIB change. Triggered updates and holddown rules further stabilize choices by damping flaps.

Step-by-Step Solution:Compare metrics: existing hop count vs. new hop count.If new hop count > existing hop count → mark as worse.RIP ignores worse paths; no RIB replacement occurs.Maintain current entry until a better or valid replacement appears.

Verification / Alternative check:Observe with debug ip rip; you will see advertisements received but not installed if their metric is inferior to the current entry.

Why Other Options Are Wrong:

• A: RIP does not keep multiple unequal-cost paths by default (RIPv2 supports equal-cost only).
• C/D/E: Replacing, deleting, or forcing refresh for a worse path contradicts RIP selection rules.

Common Pitfalls:Confusing “higher metric” with “fresher information”; freshness does not override worse metric in RIP.

Final Answer:The update will be ignored and no further action will occur.