Pass Cisco CCNA 200-301 Exam in First Attempt Easily

Welcome

1. Introduction

In this lecture, you're going to learn why passing the Cisco CCNA is such a great choice for your career. So I'm here on Monster, which is one of the biggest job sites in the UK K where I'm from, and I'm going to plug in all of the other best known entry and mid-level It qualifications that you could study for. So let's start with Microsoft MCSA and I'm going to see how many job results we're going to get for it.

If you're qualified as MCSA, there are 143 job Vacancies waiting for you today on the Monster. That's for Microsoft Windows. If you want to go into the server team, maybe you're not so interested in Windows. Let's have a look at Linux and the Red Hat certified systems administrator. So it was about 150 jobs for Microsoft MCSA. For Red hat. There's only 21 jobs. Okay, let's try other linux. There's. The Linux Professional Institute LPI.

They do qualifications as well, which are popular. Only twelve jobs for LPI. Okay, maybe Linux isn't such a good idea. How about VMware virtualization in the data center? The main qualification for that is VCP and there are 111 VCP jobs currently on the Monster website. Let me go down the list. So maybe we don't want to work in the server or the data center server team. Let's have a look at the other networking qualifications. We'll start off with Comp Tia Network Plus. Well known and popular. How many jobs have we got for that? We've got 72.

Maybe we don't want to do a vendor neutral Complication. Maybe we want to do the Juniper qualification. The JNCI is very equivalent to the CCNA. We've got 40 jobs for that. So all of these jobs are coming in around maybe 50 or 100 Vacancies right now. Maybe we are not going to do server team or networking. Maybe we want to be on security.

Security is meant to be hot this year. So let's have a search for CompTIA security. And if you've got the Security Plus qualification, there's 179 jobs waiting for you. That's a little bit higher, a little bit better still under 200.Another well-known security qualification is CEH, the certified Ethical hacker and Ch. It's way down at 22 jobs again.

Okay, so all of the other entry or midlevel popular qualifications that I could think of are coming in at under 200 Vacancies today. Most of them are around 50.A few of them are up around 150 again. Let's have a look for this Cisco CCNA then see if it's any better. OK, 513 jobs waiting for you once you've got the Cisco CCNA qualification.

So you can see from that Cisco CCNA, it's killing all of the other qualifications out there. This is the best qualification to do if you want to break into an It role. So I'm really glad to have you on the course. I'm really happy that I'm going to help you pass this qualification, it's going to make a huge difference to your career and your life.

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How to set up the lab

1. How to Set Up the Lab Introduction

This course comes with full lab exercises, so you'll get hands on practice with all of the cisco technologies that we're going to be covering.

I use the free software cisco packet tracer for the lab labs, so there's no need for you to buy any cisco equipment or any other software.

In this section, I'll show you how to set up the lab. In the first video, I'll show you how to install packet tracer. In the next video, I'll show you where to find the lab exercises in the course, how to download them, how to load them up in packet tracer, and how to use them.

2. Cisco Packet Tracer Installation

In this lecture you'll learn how to install to school Packet Tracer which is the software used for the labs. To get the software, the first thing that you have to do is sign up for the free Introduction to Package Tracer course which you can find on the Cisco Network Academy website. So I'm on the page already.

You can see the URL up here at the top and then I'm going to hover my mouse over sign up today and click on English. Then when the next page loads, I'll enter in my name here and my email address. I was created a temporary email here to doth is demo and then solve the math questions. And then I can click on Submit.

Then it tells me that they've suntan activation email to my inbox. So I will go there and I can see the message coming in now into my inbox. So I will click on that and I can see there's a link here to activate the account. So I will click on that. The next page asks me to create my [email protected] which will give me access to the Cisco Network Academy.

It's already filled my detail and my name in here for me. It asks me some additional details here including setting a password. I've already filled that in.

So now I can click on register. Then on the next page it asks me to sign in. So I'll enter my email address and then click on Next and then enter my password and I can click on Sign In. It's then going to ask me for yet more details. So I will fill all those in I have already.

And then I can click on Create account. Then I can click on Launch Cars and that will finally take me into the introduction to Packet Facer cars. So if you haven't used Packet Facer before, this course is useful. It will teach you how to build your own projects in there. I'll actually show you how to do that quickly here.

But if you want to have a longer course about that, then you can watch this introduction to Packet Trace. Of course the other thing that we can do from in here is to actually download Packet Treasure. To do that I need to click on the My net button over here on the left. I can also just go to www.netacad.com and log in there. That will bring me this page.

And under the Resources menu I can click on Download Package Tracer and then on the page here I select the version for the operating system I'm running on. You can get it for Windows, Linux or Mac. I want 64 bit Windows here. So I'm going to click that option and then that is going to download the installation file to my downloads folder.

It's 146 meg so it might take a little bit of time. I'll just give us a couple more seconds and then it will be done. And then when that is ready, I can go to my downloads folder and I can see it there. So I double click on the executable in Windows.

Click on yes to accept this. Accept the agreement. It's a very simple install. I'm basically going to just be clicking Next, next here. So I do that and then it's going to install Packet Tracer. This is going to take a little bit of time as well. So I'll pause the video again here and come back when it's done. When the installation has completed, I can click on Finish and that is going to launch Packet Tracer.

And when it finishes starting up here, it's going to ask me to log in with the same username and password again. You're going to have to do every time you use Packet pressure. It is a mild annoyance. So I'll put in my username which was [email protected], and the non the next page I'm going to put in my password in there and then I can click on Sign in and this is now going to open up Packet Tracer for me. When I open it like this, it's going to be just a blank project with nothing in there. If you do want to create your own projects, you'll see that you've got the devices down here at the bottom. So there are all of my different routers.

So I can just click on here and I can drag and drop a couple of routers into my topology. Let's say that I want a switch as well. You can see down in the bottom left, it's routers that are selected there. When I add a switch just over the right of there, it switches. I would click on that and then I can select the switch that I want and drag and drop that in as well. Then I also need to connect my devices. So I'll click on the button here. To add connections, you need to use the right type. So I'll add just straight through Ethernet connections here.

So I'm going to click that button and then I can click on my router and select the interface that I want to connect the cable to and then click on my switch and select the port I'm going to connect it to on my switch. And then I need to click on the Link button again. Each time you add a new link you need to click on the Link button again. And I'm going to select the part on my router I want to plug the cable into and then click on Switch and select the part on the switch I'm going to plug that into.

Then to actually configure your devices, you just click on them. So I'll click on my first router here and then click on the CLI tab and then that gets mean to the command line interface for that router. That's how you can quickly build your own apologies to practice with in packet tracer for this course.

You don't need to build your own apologies, because I'm going to be supplying pre built projects for every single technology that you're going to be running on the Cisco devices. And I'll show you how to use the projects that are provided the course in the next lecture.

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Host to Host communications

1. Introduction

You'll learn about the OSI reference model? The OSI Model is a conceptual framework that helps lay out how computer networking protocols should work with each other, and it really helps aid your understanding as you're learning about networking as well. Actually, this is going to form the bedrock of your understanding of networking, so it's a really important section. We'll also go into the definitions of the different layers that make up the OSI model before covering them in much more detail in later sections. Throughout the course, we will also cover the TCPIP suite and discuss how it relates to the different layers of the OSI Model.

2. A (Very) Basic Introduction to Networking

This lesson I'm going to give you a very basic introduction to networking. If you already know about switches and routers and network topology, you can just skip right on ahead to the next lesson. But if you're brand new networking, then I'm going to give you a quick overview here.So let's say that we've got an office which is in New York for our company.

In that office I'm going to have end hosts like PCs, server and a printer like you can see here. And they're going to need to be able to communicate with each other. So for that I'm going to put ina network switch and I'm going to cable my devices to that switch with Ethernet cables. And that's what a switch looks like. There's a Cisco switch.

You can see it's got a lot of parts in there so that I'm going to be able to connect in a lot of devices. The switch is what allows connectivity on my local area network in that office in New York. Maybe I've also got a laptop which is going to connect in over a wireless network. So for that I'm also going to have a wireless access point which is also going to connect into our switch. And that's what a wireless access point looks like.

So I've got all my devices in New York. Now they can all talk to each other. I've built a local area network. A local area network is a network that connects devices which are in the same local area, like in a single office or maybe a university campus. Okay, I don't just want my end host in my office to be able to talk to each other.

They're going to want to communicate with other devices out on the Internet as well. So for connectivity out there, I'm going to need a bit more of an advanced device which is a router. A router is able to make advanced routing decisions to route traffic between different areas of your network. That's why it's called router. And this is what a router looks like. You can see it's pretty similar to a switch, same kind of size. Typically, it will have less physical parts on there and it will spark different types of parts so that it can connect different types of networks as well.

Next thing we know that there's going to be bad guys out on the Internet, hackers who are going to try to attack us. So we need to guard against that. So we're going to put a firewall in place and this is what a firewall looks like. Again, you'll see that our different network devices tend to look very similar to each other, but they fulfill different tasks on the network.

The firewall secures the different parts of our network from each other. Okay, so that was our New York office for local area network and it's connected to the out to the Internet in a larger company. We’re not going to just have one office in New York. Example here, let's say we've also got an office in Boston as well. In Boston we're going to have a similar kind offset up, the same kind of devices in there. We’re going to have a local area networking Boston and we've also got local connectivity to the internet from Boston as well. Now because we're the same company, I’m going to want to have connectivity between my New York and my Boston offices. I want the end host and both of those sites to be able to communicate with each other. It is possible that they could communicate securely over the Internet if I set that up.

But another way of doing it is I could maybe put in a dedicated connection between my two routers and both sides and that's going to give me my wide area network connection between my different offices. Okay, so that's a really quick overview of networking and the point of networking is to allow that connectivity between our different end hosts on the network.

So looking now at the characteristics of a network, we've got the topology. I just go back to that previous slide. This is an example of a network topology diagram. The topology is how the devices are connected up to each other. Other characteristics is the speed of the network. Typically the faster the network is, the more it's going to cost you. And cost is itself a characteristic as well.

Things that will affect the cost or the type of devices you have in there, the size of the network, the different technologies you're using, et cetera. Other characteristics are security. I mentioned the firewall in the previous slide. We’re not going to just have security on our firewall though. We also have security features on our routers Andon our switches and we can have other security devices such as intrusion prevention systems as well.

Next we have availability. We’re going to want to make sure that our network always stays up and for mission critical components in the network, typically we don't want any single points of failures we will double up on those components so that if anyone fails, we've got an alternative component that will still be up and running. Scalability is also important. We want to design the network in such a way that it's easy for it to grow without company without requiring a redesign and reliability. Similar availability where we want to make sure again the network is going to be reliable but it's going to continue to work.

3. The OSI Reference Model Overview

This lesson you'll learn about the OSI model. The Open Systems interconnect model is a standard of the International Organization for Standardizations. So it's an ISO standard. It's generally all-purpose framework that characterizes and standardizes how computers communicate with one another over a network. So the OSI model is conceptual.

It's not a physical thing Oran actual protocol or technology. It's seven-layer approach to data transmission divides operations into specific related groups of actions at each individual layer. And a layer serves a layer above it and is served by the layer below it. I know that doesn't make much sense yet, so let's have a look at how this works in action.

So let's look at an example here. I've got a sender on the left. Let's see if it's my laptop and we've got a receiver on the right. Let's say that's my email server and we're both connected into a switch and I'm going to send an email to my email server. So obviously the sender is going to compose this traffic that's going to be sent to the receiver. And as it builds this package that is going to be sent, it's going to start off at the top level and then it’s going to work its way down to the bottom level. So at the sender, first off, it will create the layer seven information, which is the application layer. So if I'm sending an email that will contain information such as the from and the two fielded cetera, then it will encapsulate the layer seven information in the layer six information.

Layer six is the presentation layer and then it will encapsulate that in the layer five session layer information. Layers five, six and seven are known as the upper layers and they are more important for application developers rather than network engineers. Network engineers start to get really interested when we get down to layer four.

So we've got our upper layer traffic composed. That then gets encapsulated with our layer four header, which is the transport layer. Layer four, this is going to be either TCP or Upend it will include the port number such as part 80if it's web traffic, part 25 for our email example. Now, if you don't already know the details of TCP, UDP and port numbers, don't worry about it yet. We’re going to cover all this information in much greater detail in later lessons and actually throughout the entire course. Next thing that happens is that will then be encapsulated with our layer three header.

Layer three is the network layer and important information that is included there is the source and destination IP address. A network device that operates at layer three is our routers. The next thing that will happen as we compose the package is the sender will then encapsulate that information in the layer two header. Layer two is the data link layer and important information there is the Mac address. If we're sending this over an Ethernet network.

The network device that works at layer two is our switch. And finally this package is now ready that we can actually transmit it over the wire. When we do that we're down to layer one, which is the physical layer, a network device which you don’t really see anymore, which operated at layer one was Hubs. So we've now composed the packet at the center side. We’ve put it on to the wire, it's going to travel over the network and it's going to reach our receiver.

The order of operations is going to be reversed now because obviously it comes in at the physical layer. The receiver will process the packet from the bottom layer back up to the top layer now so it comes in at the physical layer. The receiver will then look at the outside header, which is the layer two header, and it will check that this packet is for it. It will check that the destination Mac address in the layer two header is its Mac address. If it's not for it, it will just discard the packet. Next up, it will continue with the encapsulation. Now it will then look at the layer three header. It will check the destination IP address and again it will check that the packet is for it.

If not, it will discard the packet. Then we carry on with our Encapsulation on the receiver. It will look at the layer four header. What this is useful for is imagine the receiver is not just an email server listening on part 25 for email traffic. Let’s say it's also a web server as well, listening on part 80 for web traffic. How does it know if this traffic is for its email server application or its web server application? It can tell by looking at the part number. Next we will carry on with the Encapsulation. We'll strip off the layer four header. We’ll look at the layer five header.

At the session layer, we'll carry on up. We will then look at the layer six header and then the layer seven header. So that's the whole thing. That’s how we got traffic from the sender to the receiver as far as the OSI model is concerned. At the sender side, again, we start off at the top layer. We work our way down to the physical layer. It goes across the physical layer. It will hit the receiver there and it will then capture going in the opposite direction, going from the bottom layer up to the top layer. Looking at the benefits we get from the OSI model, engineers don't need to design a technology to work end to end from top to bottom of the model.

They can just focus on their layer of expertise and make sure that they comply with the standards for the layers above and below. This leads to open standards and multi-vendor interoperability. For example, if you're an application developer you can just focus on the top three layers. The lower layers are the domain of network engineers. So you don't need to understand them. You just need to make sure that where you interface between layer five and layer four, you're complying with the standards there. Troubleshooting is also easier because you can analyze a problem in a logical fashion, layer by layer. It's difficult to overstate just how important the OSI model is to computer networking. As you become more experienced with networking, you'll think according to the OSI model, when you're troubleshooting or learning a new network technology, this will be natural for you.

This is what I do really, every day, on day to day basis and on the job, you'll hear technologies and problems being described according to their OSI layer. For example, if you're troubleshooting a problem and you start looking at it in an overly complicated way, it might turn out that it was just because the cable was unplugged and you would see if the guy next to you, oh yeah, it was a layer one problem. You might also hear of a layer eight problem that’s when a user has made a mistake. Okay, this is going to be tested heavily on the exam.

And like I just said in the last slide, it’s really important anyway, not just for exam purposes. For your whole understanding of networking, you really need to know the OSI model. It’s going to help you. So we are going to have acronyms that are going to help us remember what the actual names of the different layers are. The classic acronym that you'll see in all the books going back years and years is Please Do Not Throw Sausage Pizza away.

So again, the layers were the physical layer, then the data link, then the network, then the transport, the session, the presentation, and the application layer when you're first beginning. In fact, to be honest with you, I still remember it from the acronym. And it's just automatic for media know it's please do not throw sausage pizza away. That helps me easily remember what the names of the different layers are and what order they come in.

Other acronyms you can use if you don’t like that one that's relevant to networking is Please don't need those stupid packets. Anyway, another one that would be relevant to us here is Please do not teach students pointless acronyms. And a useful one please do not take salespeople's advice. If you've been working in networking for anytime already, you know that's great advice. And my personal favorite please do not to talk Superman's private area. I think an upset about that.

4. The TCP/IP Stack

In this lesson you'll learn about the TCP IP suite. TCP IP was developed way back in the 1960s by the US. Department of Defense's advanced research project. That's DARPA. It's a protocol stack which consists of multiple protocols, including TCP, which is the Transmission Control protocol, and IP, which is the Internet protocol. So it's not a single protocol, it's a protocol stack. What a protocol is, if you think of diplomats, when diplomats from different countries meet each other, there's a certain way that they're expected to behave and to communicate with each other. In computer networking, protocols basically mean the same thing. So if we've got two hosts and they're going to communicate with each other, there's going to beat protocol which is going to control how that communication should behave, how it should work.

TCP IP, it's the main protocol stack used in computer operations today. There used to be other competing protocols way back in the day, like IPX SPX and Apple Talk, but they're really dead now. TCP.IP is now ubiquitous. And whereas the OSI reference model is conceptual, the TCP IP stack is actually used to transfer data into the production networks.

TCP IP is also layered, but it doesn't use all of the OSI layers, though the layers are equivalent in operation and function, so it does actually use them. But in the documentation, it only lays out four different layers. Let's look at those now. So you can see on the slide here, over on the left we've got the OSI model that we covered in the last lesson. So we've got the seven layers there. Remember later, remember easy way is please do not throw sausage pizza away.

So we've got physical data link, network, transport, session, presentation, and application. Over on the right we've got the TCP IP stack. So you can see we've only got four different layers there. Up at the top we've got the application layer, which maps to all three of the application, presentation, and session layers in the OSI model. Below that we've got the transport layer, which is a one to one mapping with the transport layer also in the OSI model.

Underneath that we've got the Internet layer, which is equivalent to the network layer in the OSI model. And down at the bottom we've got the network access layer, which maps to the data link layer and the physical layer in the OSI model. Now, I was saying in the last lesson it’s really important to understand the OSI model, the TCP IP stacks, for sure. If you're working in networking, you're going to know the different protocols like TCP and Liplike the back of your hand.

But when we're talking to other network engineers, it's more commonly the OSI model that we're going to be referencing, moving on, looking at some host communications terminology. So when two hosts talk to each other, they’re going to be exchanging PDUs protocol data units. The PDU is the entire communication all the way from layer seven down to layer one of the OSI stack.

We can also divide that into different terms depending on which layer of the TCP IP suite we're talking about. For communications up at the application layer, that's called data. For communications between the transport layer on two different hosts, that's called segments. Between the Internet layer, those are our packets, and down at the network access layer, those are our frames.

You know, just in the last slide, I was saying, typically real world, we're not going to be discussing theTCP IP stack like this about the four layers. More commonly, we will use the OSI seven layers. But on this slide, the terminology actually is commonly used. So if I'm talking about layer two, communications, I'll call that a frame. If I'm talking about layer three, I'll call it a packet, and if I'm talking about layer four, I will call it a segment.

Another thing I need to tell you here is that packet officially as a layer three. But you might have heard me talking earlier on in this section and calling the communication between two hosts a packet. So really the correct term is a PDU. But in day to day conversation, often we’ll just call communications between two hosts packet, meaning the entire stack.

5. The Upper OSI Layers

In this lecture, you'll learn about the upper layers of the OSI model. That the upper three layers five, six, and seven. Network engineers don't typically work directly with those upper three layers. The OSI model, they're more relevant to application developers. But we still need to know what they do.And for the exam, we need to know the definitions of each of the layers as well. It’s quite likely that you'll be tested on that.

So in this lecture, that's primarily what I'm going to be doing is giving you the Cisco definitions so you'll be ready for the exam. Information included in the upper layers would include the message body and the subject line in an email message, for example. So let's look at the three top layers, starting with layer seven, the Application layer. This provides network services to the applications of the end user.It differs from the other layers and that it does not provide services to any other OSI layer.

The application layer establishes the availability of intended communication partners. Intended communication partners would be the host that this host is communicating with. If you remember from the lecture before, we were discussing the OSI model, you saw that straight line between two hosts at the same layer of the OSI stack.

So the application, where it establishes the availability of intended communication partners, that's a straight line going to the other host. It then synchronizes and establishes agreement on procedures for error recovery and control of data integrity. Data integrity means checking the data has not been altered or corrupted in transit.

The next layer is layer six, the Presentation layer. This ensures that the information that is sent in the application layer of one system is readable by the application layer of another system. The presentation layer can translate among multiple data formats using a common format. For example, we might need to do this for computers with different encoding schemes. And the last layer of our upper layers is layer five, the Session layer.

This establishes, manages and terminates sessions between two communicating hosts. The Session layer also synchronizes dialogue between the presentation layer of the two hosts and manages for data exchange.

For example, we might have web servers which have got many users that are using that web server. So in that case, we would have multiple incoming sessions.

The Session layer keeps track of all of those. It also offers efficient data transfer class of service, which is similar to efficient data transfer and exception reporting of upper layer problems. Okay, so that's the definitions of the upper layers. We will go into the definitions of the bottom four layers in.

6. The Lower OSI Layers

In this lecture you'll learn about the bottom four OSI layers. Where network engineers are not typically very concerned with the top three layers, we are very concerned with the bottom bottom four layers. This is really bread and butter stuff for us. Each of these bottom four layers are so important that they're going to have their own dedicated section later on in the course.

Here I'm going to focus on giving you the definitions which you're going to need to know for the exam. So the first of the bottom four layers will start with layer four, which is the transport layer. The main characteristics of this layer are whether TCP or UDP transport is going to be used and the port number. Now, if you don't know anything about TCP or Dupo port numbers already, don't worry about it too much for now because we're going to be covering this in the dedicated section for layer four layer. For now, you just need to know that if we want the communication between the two hosts to be reliable, then we'll use TCP.

If speed is more important than reliability, like for voice or video traffic, then we'll use UDP instead. The other main characteristic this layer is the part number. For example, part number 80 for Http web traffic, part number 25 for SMTP email. Now, there is quite a lot of other information also in the layer four header, but we'll talk about that when we get to that particular section in the course. The definition for layer four, the transport layer, defines services to segment, transfer and reassemble the data for individual communications between the end devices.

It breaks down large files into smaller segments that are less likely to incur transmission problems. The next layer is layer three, the network layer. The most important information at the network layer is the source and destination IP address. Again, there's a lot of other information also carried in the layer three header, but we'll talk about that when we get to the later section. Routers are layer three devices. They operate at layer three of the OSI model and the definition of a network layer.

It provides connectivity and path selection between two host systems that maybe located on geographically separated networks. The network layer is the layer that manages the connectivity of hosts by providing logical addressing. IP addressing is our logical addressing. Next layer is layer two, the data link layer. The most important information here is the source and destination layer two address. Again, just like with layer three and four, there is other information also included in the layer two header.

For example, the source and destination Mac address. If Ethernet is the layer two technology, different layer two technologies use different formats for their addressing. For example, old Legacy Frame Relay uses DLC or Dulce numbers for the addressing with Ethernet, which is what is always used in our local area networks. It’s the Mac address that is used here, and switches operate at layer two. Our switches are layer two aware Devices the definition for the data link layer. It defines how data is formatted for transmission and how access to the physical media is controlled.

It also typically includes error detection and correction to ensure a reliable delivery of the data. And finally, we have layer one, the physical layer. This concerns, literally, the physical components of the network. For example, the actual physical cables being used.

Definition of the physical layer. It enables bit transmission, the one sand those between end devices. It defines specifications needed for activating, maintaining and deactivating the physical link between end devices, for example, voltage levels, physical data rates, maximum transmission distances and physical connectors, et cetera. Okay, so there you have it. That was the quick overview and mainly the definition of the bottom four layers. As we go through the rest of the course, we’ll be covering those in much more detail.

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