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In the last lecture we discussed about both topology and star topology.

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Now, let us see about ring topology in this type of topology, each computer is directly connected

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to the other computers within the same network.

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Now, as you can see on the screen, the networks data flows from computer to computer, back to the

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source.

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The ring topology has a lot in common with the topology because if you want to add a network, you have

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no choice but to break the cable ring, which is likely to bring down the entire network.

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This is one big reason that ring topology isn't very popular.

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You just won't run into a lot as I did in the 1980s and early 1990s, where this type of topology was

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popular.

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It's also pricey because you need to several cables to connect each computer.

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It's really hard to reconfigure.

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Now, let's say there are 50 pieces in the ring topology, and if you want to add a new piece, you

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just have to cut one cable.

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And that is why it would require a lot of time and that would bring down the entire topology.

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But even with that all being said, if you work at an Internet service provider that is ISP, you may

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still find a physical ring topology in use for the technology called Sonnett or some other one technology.

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However, you just won't find any local area network having a physical rings anymore.

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Also, since one computer goes down, ring topology is easier to troubleshoot, but as I said, it provides

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less fault tolerance because if one of the pieces goes down, the entire network goes down.

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Next ahead is Mr..

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Now, in this type of topology, you will find that there is a part from every machine to every other

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one in the network.

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That's a lot of connections, in fact, I can tell you that the methodology can win the prize for most

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physical connections per device.

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You will never find a missed apology in local area networks anyway.

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If ever these days, but you will find a modified version of it known as the hybrid apology used in

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the wide area networks, including the Internet.

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Now, often hybrid mesh topologies will have quite a few connections between certain places to create

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redundancy.

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As you can see on the screen, there are four computers and all of all computers have their wires connected

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to other remaining three computers.

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Now, from this weekend, some of a formula for each and locations or and hosts you can have and in

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duplicate and minus one upon two connections.

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In our case, there are four hosts.

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So let us put the value and is equal to four in the equation and we can get that four into Blackgate

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four minus one upon two.

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That is six connections.

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And you can see on the screen that there are six wires in total.

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In methodology, there are a lot of connections, as I said, if there are 50 computers, then 15 to

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bracket 50 minus one of one two.

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That is a lot of connections.

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Next, since there are a lot of connections, we required more number of wires and it's a pricey topology

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to install, and that is why mesh topology is not a common topology.

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But if one computer fails, we can troubleshoot it quickly because that computer's cables will fail

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and we'll get to know that this PC is not working.

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But apart from all of the advantages and disadvantages, we can see that mesh topology provides a robust

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for tolerance.

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Even if one PC fails, the remaining network can communicate with other PCs.

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Whereas in the case of ring topology, if one PC fails, the entire network goes down.

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And that is why Mesh Toppo hybrid mesh topology is preferred these days in the Internet.

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In the next lecture will talk about another two types of topologies, which is point-to-point, topology

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and point to multipoint topology.

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Also, we will see how to select the right topology based on five to six factors, which I will be determining

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in the next lecture.

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Before moving ahead, I would like to tell you that if you are liking our lectures and if you are understanding

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