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smart Z

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RIP routing table

Hi Experts,

I have this snapshot and i want to know which route will be on the router table. How does it determine.

Thank you.
Router-RIP.png
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David Akinsanya
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RIP uses hop count

192.168.2.0     via S0/0     192.168.255.26     1 hop count
192.168.255.16     via S0/0    192.168.255.26      1 hop count

Actual Statement will show something like this
R    192.168.2.0/24 [120/1] via 192.168.255.26, 00:00:26, Serial0/0
R    192.168.255.0/24 [120/1] via 192.168.255.26, 00:00:26, Serial0/0

Breakdown
R = Indicates that it is a route learnt via RIP
192.168.2.0 = Is the network learnt
120 = Is the Administrative Distance for RIP
1 = Is the number of hops to the network learnt
192.168.255.26 = Is the next hops interface ip address that the router needs to ply if it wants to reach the network learnt
Serial0/0 = Is the interface on the Router through which to exit when attempting to reach the network learnt.


For FYI
OSPF uses cost
EIGRP uses Metric

Hope this helps
All the best
Avatar of smart Z
smart Z

ASKER

can you check again I was thinking it gets update frm S0/1? I know you are correct though.
RIP is a per hop metric so according to your SS the router will use 192.168.255.26 as the gateway for network 192.168.2.0 since the hop count is 1.

The route to 192.168.255.16 is a bit more complex since it has equal cost routes. According to RFC it should use the first route learned but because cisco can do load balancing across equal cost routes with CEF it might use both. Also because you are using RIP V1 which is classful you may not end up with either route in your route table depending on the subnet mask of the interface the update is received on.

Load Balancing info
http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094820.shtml
ASKER CERTIFIED SOLUTION
Avatar of David Akinsanya
David Akinsanya
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