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In this last lecture of network topologies, we are going to see two different types of topologies that

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is point-to-point apology and point to multipoint apology.

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So let us see what is Point-to-point apology?

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You can see the image on the left hand side of the screen.

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Just focus on that for a few couple of minutes.

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Now, as its name implies, in a Point-to-point apology, you have a direct connection between two routers

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or switches, giving you one communication part the routers in a point-to-point.

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Topology can be linked by a series of cable, making it a physical network or if they are located far

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apart and connected only by a circuit within a frame.

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Really, it's a logical network and still not a figure on the screen.

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Illustrates three examples of typical P1 or wide area network point to point connection.

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What you see in the first part is a lightning bolt and a couple of round things that a bunch of arrows

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projecting from them, right?

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Well, the two round things, radiating arrows represent our networks to routers.

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And that lightning bolt represents a van link.

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Now, these symbols are industry standard, and I'll be using them throughout this course, so it's

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a good idea to get used to them.

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OK, so part two of the diagram on the left hand side shows two computers connected by a cable, a point

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to point link.

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Now, by the way, this should remind you of something we just went to do.

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Remember peer to peer networks that we have seen in earlier of this section.

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I hope you remember that good.

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Now, I hope you also remember that a big drawback to Peer-to-peer network sharing is that it's not

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very scalable.

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Now, with this thing in mind, you probably won't be at all surprised that even if both these machines

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have a wireless point-to-point connection, this network still won't be scalable.

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You'll usually find Point-to-point networks within many of today's wide area networks, and as you can

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see in the part three of the diagram on the left hand side, a link from a computer to a hub or a switch

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is also a valid point to point connection.

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A common version of this setup consists of a direct wireless link between two wireless bridges.

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Now, just focus on the figure that is on the right hand side of the screen, that is point to point,

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that is point to multipoint topology, again, as a name suggests, a point to multipoint topology consists

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of a succession of connections between an interface on one router and multiple destinations around one

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point of connection to multiple points of connection.

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Now, each of the routers and every one of the interfaces involved in the Point-to-point connection

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are part of the same network.

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The figure on the right hand side shows a wide area network and demonstrates a point to multipoint network.

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You clearly see a cable corporate router connecting to multiple routers of the branch offices.

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That and the figure on the left hand side are the two different types of topologies that you need to

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remember.

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Now, a hybrid topology is a topology that is a combination of two or more physical or logical network

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topologies working together within the same network.

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Now, how to select the right topology.

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Now you can just ask the question, well, we are just connecting cables between two hosts, so why

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do we need to actually think of at this point wrong?

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Regardless of the type of the network you build, you need to start thinking about the quality at the

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bottom and work up.

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Now, I will give you a real live example and make sure you listen to it.

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Think of it as if you were at an electronics store buying the cable for your home theater system.

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You have already spent a bunch of time and money getting the right components to meet your needs.

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Because you've probably partied with a hefty chunk of change, you might be tempted to cut corners,

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but why would you stop now and collect all your high quality devices together with the cable equivalent

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of Doyne?

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No, you are smarter than that.

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You know that picking out the exact cable that will maximize the sound and the picture quality of the

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specific components can also protect them, right?

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It is the same thing when you're faced with selecting the physical media for a specific network.

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As you know, not only you have a buffet of network topologies to choose from, but each one has its

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pros and cons before implementing it, but it really comes down to that well-known advantage.

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Ask the right questions.

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How much cash do you have?

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How much fault tolerance and security you really need?

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Also, is this network likely to grow like a weed that you need to quickly and easily reconfigure often?

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In other words, how scalable does your network need to be?

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For instance, if your challenge is to design a nice, cost effective solution that involves only a

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few computers in the room, getting a wireless access point and some wireless network cards is definitely

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your best way to go because you won't need to part with the cash for a bunch of cabling.

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And that's super easy to set up.

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Now, let's say if you hired a person to design a network for an Internet service provider running at

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ninety nine point nine percent of the time, you need a Godzilla strength for tolerance.

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So your primary solution is to either go with a hybrid or a partial apology.

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Now, again, remember that in enmeshed topology, there are a subset of them into bracket and minus

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two connections.

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So, again, if you implement mesh topology, the cost would also go up.

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So here's a list of things to keep in mind when you're faced with coming up with the right topology

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for the right network.

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First question is to ask, what is the cost of the installation?

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What is your budget?

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Do you have enough amount of money in your pocket to spend?

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The next question is ease of installation.

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Check the room, check the network size before selecting the topology.

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The next is ease of maintenance.

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Are you going to select topology that is difficult to maintain?

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Absolutely not.

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We are going to select the topology that is a whole lot easier to maintain.

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The fourth question that you need to ask is, what is the fault tolerance of the topology?

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Now, if you have around 10 to 15 computers and you select ring topology, then that's a bad call.

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Ring topology provides the least for tolerance.

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So before selecting the right topology, you need to ask the question of fault tolerance.

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And finally, security requirements.

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Now, these five factors you should always consider before you select the right topology for your network.

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That's it, folks.

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This is all for the network topologies.

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And I hope you are learning a great content from this course.