TCP/IP OverviewWhen designing network applications, one key protocol stands out as the foundation to make this possible. This protocol is TCP/IP. There are many protocols that allow two applications to communicate. What makes TCP/IP an interesting protocol is that it allows applications on two physically separate computers to communicate. What makes TCP/IP great is that it can work with two computers in one room or across the world. In this article I'll show you how TCP/IP allows a wide range of computer hardware to work together without ever having to know what the other machine is or how it works. At the same time you will learn how it allows information to travel around the world in a fraction of a second without knowing in advance how to get there. Before we get too far it's worth noting that TCP/IP is actually made up of two protocols. The first is the Transmission Control Protocol or TCP. The second protocol is IP which stands for Internet Protocol. These two together provide the basis for the virtual layer of most networks we use today. The roots of the protocols date back to the 1970s. At the time, networks were built with cables that directly connected one computer to another. This is called direct connection. If you wanted information to reach a computer that yours wasn't directly connected to, you would need to create a bridge on a common machine that you are both connected to. This allows messages you send on one connection to be transferred to the computer on the other connection and sent to the computer you were trying to talk to. This is sometimes called a gateway. In 1973 the Defense Advanced Research Projects Agency (DARPA) commissioned two engineers to design a way for information to travel more easily between these early networks...... middle of paper...... ackages.This pair of protocols is the workhorse of the modern Internet. According to Microsoft this is “largely due to its ability to connect networks of different sizes and systems of different types together”. (“Understanding the Basics of TCP/IP Addressing and Subnetting” September 23, 2011) Before TCP/IP came along, machines had to be physically compatible in order to exchange messages with each other. Now the physical layer has been abstracted and messages travel at the logical layer. The physical layer is still present but is now a resolved problem space that allows developers to focus more on applications. This has become the true success story of TCP/IP.Works CitedMicrosoft Inc., “Understanding the Fundamentals of TCP/IP Addressing and Subnetting.” Last modified: September 23, 2011. Accessed September 24, 2011. http://support.microsoft.com/kb/164015.