TCP/IP and Networking Fundamentals for IT Pros

Introduction to TCP/IP and Networking Fundamentals
Welcome to TrainSignal. My name is Ed Liberman, and you're watching a video series called "TCP/IP and Networking Fundamentals". This series has eight videos, and they are "What is a Protocol? ", "What is TCP/IP? " "Configuring an IP Address", "IP Address Planning", "Binary Numbers", "Internetworking", "Classless Interdomain Routing", and "Fundamentals of IP version six". So sit back, relax, and I hope you enjoy these videos.

What is a Protocol?
Welcome to TrainSignal. You're watching a video called What is a Protocol? In this video, we're going to learn exactly what a protocol is, and how it's used by computers to allow them to communicate on a network. Then we're going to take a look at something called the OSI Model, to help further our understanding of protocols. Now, if you've ever tried learning about the OSI Model before, or maybe you had heard from somebody about the OSI Model and how difficult it was to understand, don't worry. I'm going to give you a very simple way to understand what it is and how it works.

IP Address Planning
Welcome to TrainSignal. You're watching a video on IP address planning. In this video, We're going to start off by asking some questions that will help us to plan an IP addressing scheme. Then, we'll take a look at some of the basic rules for IP addressing. We'll talk about classful IP addressing. We'll see the difference between private and public IP addressing, and then we'll learn what network address translation or NAT is. Let's start off by addressing a major question, which is how do I plan an IP addressing scheme for my network? See, there are so many choices out there when it comes to IP addressing, how do I know what to do? Well there are three questions that you can ask yourself that should help you come up with a solution. And the first question is how many IP addresses do you need right now? How many computers are currently on your network? The second question, how many IP addresses will you need in the future? This is a very important question that a lot of IT administrators forget to ask themselves. You really need to not just plan for, let's say, the 50 computers you have on your network right now, because those 50 could become 500 in no time at all. So always plan for some degree of growth. And the third question is, are you dealing with a preexisting IP scheme? It's very rare that we get the opportunity to walk into a network and start from scratch. Usually, there is something in place right now, and then we have to figure out how to make a change to that existing scheme. So these are three very important questions that all IT administrators should ask themselves before planning out an IP addressing scheme for their network.

Binary Numbers
Welcome to Train Signal. In this video, we're going to learn all about binary numbers. Now first, before we get into the binary stuff, I've got a question for you. What is this number right here? Go on, tell me. It's not a trick question. That's right, 3, 482. But how do we know that? Well, we know that because we've learned that in the decimal numbering system, each column has a value, right? We have the one's column, the 10's column, the 100's column and the 1, 000's column. And then we take the number in each column and multiply it by its value, so here we have three times 1, 000 being 3, 000, four times 100 is 400, eight times 10 is 80, and two times one is two. We then add those numbers together and you end up with, well, we were right, 3, 482. All right, now before you get upset and turn off the video, sounds like a bunch of double talk, I promise you that there was a purpose behind this and this is going to help teach you how to work with binary numbers.

Internetworking
Welcome to TrainSignal. This video is about internetworking. In this video we'll go back and review, briefly, what an IP address is and how it's broken apart. So we can then take a look at what a router and Default Gateway are, and then I'll give you a basic introduction into Subnetting. First, let's make sure we understand what an IP address is. And IP address is a 32 bit address which is divided into four eight bit octets. We typically see it as four numbers separated by dots. The Network ID portion of the IP Address, which we know is always on the left, is what identifies what network a computer is on. Whereas, the host ID, which is the right portion of the IP Address, will uniquely identify the computer within that network. Let's take a look at an example. Here a have an IP Address of 192. 168. 10. 101, and as I mentioned before, we know that the Network ID is on the left, and the Host ID is on the right. But we don't know how to divide it up by just looking at the IP Address. We need to add in something called the Subnet Mask. The Subnet Mask is made up of 255s and zeros, and the 255s establish what portion is the Network ID, and the zero, or zeros, as it could be, would define what portion is the Host ID. So in this example, 192. 168. 10 would then be the Network ID, and 101 would be the Host ID. Now, it's very important to understand what network a computer is on when it comes to understanding internetworking. Now, we'll come back to that in just a few minutes but first. . .

CIDR
Welcome to TrainSignal. In this video, we're going to talk about Classless Interdomain Routing, or what's more commonly known by the acronym CIDR. I say the letters because I pronounce this acronym "cider" but many people pronounce it "sitter, " and I've even seen it pronounced as "cedar. " Cider, sitter, cedar, don't really care what you call it. That's what we're going to talk about in this video. So we're going to start off by going over some of the problems that we have with Classful IP Addressing. Then we'll get into what CIDR and VLSM really are. And VLSM I will tell you stands for Variable Length Subnet Masks. And then we'll see how to Subnet using CIDR.