Computer Communications and Networks (saylor.org)

The Internet has become one of the most important components of our life. We browse the Web, check e-mails, make VoIP phone calls, and have video conferences via computers. All of these applications are made possible by networking computers together, and this complex network of computers is usually referred to as the Internet. This course is designed to give you a clear understanding of how networks, from in-home local area networks, or LANS, to the massive and global Internet, are built and how they allow us to use computers to share information and communicate with one another.

Unit 1 introduces you to an explanation of what computer networks are as well as to some basic terminology fundamental to understanding computer networks. You will also familiarize yourself with the concept of layers, which compose the framework around which networks are built. Next, Unit 2 explains the concept of protocols. A computer communication (or network) protocol defines rules and conventions for communication between network devices.

The rest of the course implements a top-down approach to teach you the details about each layer and the relevant protocols used in computer networks. Beginning in Unit 3, you will explore the concept of application layer protocols, which include the Domain Name System, e-mail protocols, and the Hypertext Transfer Protocol. Unit 3 ends with an overview of how to use socket programming to develop network applications. In Unit 4, you will learn transport layer protocols, including the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP). You will go on to study the network layer Internet Protocol (IP) and packet routing protocols in Unit 5. Next is Unit 6, which is devoted to a discussion on link layer protocols, and the course concludes with an overview on voice and video protocols, network security, and cloud computing in Unit 7.

Upon successful completion of this course, you will be able to:

- describe the architecture of a computer network and explain how each device in a network communicates with each other;

- describe the processes in each layer of the network protocol that enables different networks to share resources;

- describe the basic network protocols in each layer of a TCP/IP stack and the purpose of each protocol;

- recognize and differentiate between the various services and functionalities of specific mechanisms in each protocol and their usage in a computer network;

- explain the role of the Network Request for Comment (RFC);

- compare and contrast each layer in the TCP/IP model with those in the OSI model;

- define socket programming and explain its role in application processing;

- describe IP addressing and explain its purpose;

- explain packet collisions and how they are corrected in the link layer;

- define CSMA and describe its use in the link layer;

- describe and compare application protocols such as VoIP and IPTV; and

- explain TCP/IP security related issues.