Free IP addressing and routing lessonsIP addressing and routing · Stage 1 · Forwarding and routing · Step 1
Forwarding and longest-prefix match
See how a router chooses an outgoing interface from its table when several entries match. About 13 minutes.
A router has routes for 192.168.0.0/16 and 192.168.5.0/24. A packet is for 192.168.5.20. Which route is used?
- A192.168.5.0/24, because it is the longest matching prefix
- B192.168.0.0/16, because it was added first
- CEither: they're equivalent
Show the answer
192.168.5.0/24, because it is the longest matching prefix. Both match; the more specific one wins.
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