1
00:00:00,000 --> 00:00:07,000
Routing protocols use different criteria to determine the best path to a destination.

2
00:00:07,000 --> 00:00:11,000
As an example with static routes the administrator

3
00:00:11,000 --> 00:00:15,000
decides which path the traffic will take.

4
00:00:15,000 --> 00:00:20,000
With RIP, hop count is the determining factor or criteria

5
00:00:20,000 --> 00:00:25,000
and with OSPF, bandwidth is the determining factor.

6
00:00:25,000 --> 00:00:31,000
We as humans do this all the time when driving from point A to point B

7
00:00:31,000 --> 00:00:36,000
we will determine the best path to take based on criteria,

8
00:00:36,000 --> 00:00:40,000
such as the speed limit, congestion on a highway

9
00:00:40,000 --> 00:00:43,000
or motorway, the amount of time we have

10
00:00:43,000 --> 00:00:48,000
and perhaps some other criteria. Essentially you are working out

11
00:00:48,000 --> 00:00:51,000
the best route to take from point A to point B

12
00:00:51,000 --> 00:00:55,000
based on some criteria that’s important to you,

13
00:00:55,000 --> 00:01:02,000
typically to get from point A to point B in the shortest time possible.

14
00:01:02,000 --> 00:01:04,000
In the same way in this topology,

15
00:01:04,000 --> 00:01:09,000
when traffic is sent from San Francisco to San Jose

16
00:01:09,000 --> 00:01:12,000
which path will the traffic take?

17
00:01:12,000 --> 00:01:16,000
As an example, when using the RIP routing protocol,

18
00:01:16,000 --> 00:01:21,000
RIP would send the traffic directly from San Francisco to San Jose.

19
00:01:21,000 --> 00:01:24,000
RIP doesn’t take bandwidth into account, 

20
00:01:24,000 --> 00:01:28,000
so if we had a network of 10.1.1.0 in San Francisco

21
00:01:28,000 --> 00:01:32,000
and a network of 10.1.2.0 in San Jose

22
00:01:32,000 --> 00:01:37,000
RIP would take the direct path between those 2 networks

23
00:01:37,000 --> 00:01:43,000
and that’s because the number of hops is less than going via New York.

24
00:01:43,000 --> 00:01:46,000
RIP will not send traffic via New York

25
00:01:46,000 --> 00:01:51,000
it would send the traffic directly between San Francisco and San Jose.

26
00:01:51,000 --> 00:01:56,000
RIP, however, is not considering the bandwidth of the links

27
00:01:56,000 --> 00:01:58,000
so even though there are fewer hops

28
00:01:58,000 --> 00:02:03,000
it may be quicker to send the traffic via New York rather than directly.

29
00:02:03,000 --> 00:02:07,000
OSPF, on the other hand, takes bandwidth into account.

30
00:02:07,000 --> 00:02:12,000
So, in this case, OSPF would send the traffic via New York

31
00:02:12,000 --> 00:02:15,000
because the link speeds are greater.

32
00:02:15,000 --> 00:02:20,000
OSPF is a more powerful routing protocol and makes better decisions

33
00:02:20,000 --> 00:02:24,000
because it takes bandwidth into account when determining the best path.

34
00:02:24,000 --> 00:02:30,000
RIP doesn’t, it simply looks at the number of hops from point A to point B.

35
00:02:30,000 --> 00:02:33,000
This is a very basic topology

36
00:02:33,000 --> 00:02:38,000
simply used as an example to show you how routing protocols

37
00:02:38,000 --> 00:02:41,000
determine the best path or best route to a destination.

38
00:02:41,000 --> 00:02:44,000
The moral of the story is as follows:

39
00:02:44,000 --> 00:02:48,000
different routing protocols have different criteria

40
00:02:48,000 --> 00:02:51,000
to determine the best path from A to B.

41
00:02:51,000 --> 00:02:57,000
OSPF once again takes bandwidth into account when determining the best path.

42
00:02:57,000 --> 00:03:04,000
RIP doesn’t, some routing protocols will make better decisions than other routing
protocols.

43
00:03:04,000 --> 00:03:12,000
Generally, today you’re going to use either OSPF or EIGRP in most enterprise networks.

44
00:03:12,000 --> 00:03:17,000
EIGRP is a popular routing protocol when you have a Cisco-only network.

45
00:03:17,000 --> 00:03:22,000
EIGRP is a proprietary Cisco routing protocol

46
00:03:22,000 --> 00:03:25,000
and may not be supported by other vendors

47
00:03:25,000 --> 00:03:28,000
OSPF is an industry standard routing protocol

48
00:03:28,000 --> 00:03:33,000
and is therefore better to use when you have a multi-vendor network.