Two directly connected routers are configured only with RIP routing. If a router receives a RIP update advertising a higher hop count to a network that already exists in its routing table with a lower hop count, what does the router do with the update?

Introduction / Context:
Distance vector routing protocols such as RIP maintain a simple routing table based on hop count metrics. When a router already has a route to a destination, it may receive new advertisements with different metrics for that same network. Understanding how RIP handles updates that have worse metrics is important for predicting and troubleshooting routing decisions.

Given Data / Assumptions:

• Two routers are running only RIP, with no other routing protocols or static routes involved.
• One router already has a route to a specific network with a certain hop count.
• The same router then receives a new RIP update advertising that network with a higher hop count.
• The routers are functioning correctly and are not in a hold down state for this route.

Concept / Approach:
In RIP, the best path to a network is the one with the lowest hop count. When a router receives a new RIP update for a route it already knows, it compares the new hop count with the existing metric. If the new metric is better (lower), the router updates its routing table. If the new metric is worse (higher), the router normally ignores the update and keeps the better route. This behaviour helps maintain stability and prevents unnecessary changes to the routing table when inferior paths are advertised.

Step-by-Step Solution:
Step 1: The router has an existing RIP route to a destination network with a hop count of N.Step 2: It receives a new RIP advertisement for the same network with hop count M.Step 3: The router compares M with N. By the question, M is greater than N, so the new route is a worse path.Step 4: Because the existing route has the lower hop count, the router keeps the current entry and discards the higher metric update.Step 5: The routing table therefore remains unchanged, and traffic continues to use the lower hop count path.

Verification / Alternative check:
You can see this behaviour in a lab by configuring redundant paths and allowing RIP to converge. When you artificially increase the hop count on one path, routers will keep using the lower hop count route and ignore the higher metric updates. Commands such as show ip route and debug ip rip help confirm this behaviour.

Why Other Options Are Wrong:
Option A describes a load balancing scenario, but RIP load balancing occurs only over routes with equal metrics, not higher ones.Option C is incorrect because RIP does not replace a better route with a worse one based solely on a new update.Option D suggests a drastic action of deleting the route and forcing reconvergence, which is not how RIP normally behaves.Option E describes route poisoning and unreachable metrics, which occur when a route fails, not simply when a worse metric is advertised.

Common Pitfalls:
Some learners assume that any new update overrides the old one, but distance vector protocols compare metrics before deciding. Remember that for RIP, lower hop count is always better, and higher hop count advertisements for an already known route are usually ignored.

Final Answer:
The router ignores the update and keeps the existing lower cost route in the routing table.