Welcome to CS402: Computer Communications and Networks
Specific information about this course and its requirements can be found below. For more general information about taking Saylor Academy courses, including information about Community and Academic Codes of Conduct, please read the Student Handbook.
Explore the hardware, software, and architectural components involved in computer communications in local area networks. Topics include the basics of computer networks, switching, routing, protocols, and security.
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.
As you move through the course, take time to notice how the layers build on top of one another and work together to create the amazing tool of computer networks, which many of us depend upon daily.
This course includes the following units:
- Unit 1: Networking Fundamentals
- Unit 2: The Basics of Protocols
- Unit 3: The Application Layer
- Unit 4: The Transport Layer (TCP/UDP)
- Unit 5: The Network Layer
- Unit 6: The Link Layer
- Unit 7: Multimedia, Security, and Cloud Computation over the Internet
Course Learning Outcomes
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 basic network protocols in each layer of a transmission control protocol/Internet protocol (TCP/IP) stack and compare with its counterpart Open Systems Interconnection (OSI) layer;
- classify and configure Internet Protocol (IP) addresses, explain their purpose, and use them in complex computer networks ;
- illustrate the use of subnetting and supernetting and use the technique to divide a large network into smaller logical subnetworks;
- describe and compare the different link layer access mechanisms, protocols, and technologies;
- list, describe, and compare application layer protocols; and
- apply network techniques to create wide area networks.
Throughout this course, you will also see learning outcomes in each unit. You can use those learning outcomes to help organize your studies and gauge your progress.
The primary learning materials for this course are articles, lectures, and videos.
All course materials are free to access and can be found in each unit of the course. Pay close attention to the notes that accompany these course materials, as they will tell you what to focus on in each resource, and will help you to understand how the learning materials fit into the course as a whole. You can also see a list of all the learning materials in this course by clicking on Resources in the navigation bar.
Evaluation and Minimum Passing Score
Only the final exam is considered when awarding you a grade for this course. In order to pass this course, you will need to earn a 70% or higher on the final exam. Your score on the exam will be calculated as soon as you complete it. If you do not pass the exam on your first try, you may take it again as many times as you want, with a 7-day waiting period between each attempt. Once you have successfully passed the final exam you will be awarded a free Course Completion Certificate.
There are also end-of-unit assessments in this course. These are designed to help you study, and do not factor into your final course grade. You can take these as many times as you want until you understand the concepts and material covered. You can see all of these assessments by clicking on Quizzes in the course's navigation bar.
Earning College Credit
This course is eligible for college credit via Saylor Academy's Direct Credit Program. If you want to earn college credit, you must take and pass the Direct Credit final exam. That exam will be password protected and requires a proctor. If you pass the Direct Credit exam, you will receive a Proctor Verified Course Certificate and be eligible to earn an official transcript. For more information about applying for college credit, review the guide to college credit opportunities. Be sure to check the section on proctoring for details like fees and technical requirements.
There is a 14-day waiting period between attempts of the Direct Credit final exam. There is no waiting period between attempts for the not-for-credit exam and the Direct Credit exam. You may only attempt each Direct Credit final exam a maximum of 3 times. Be sure to study in between each attempt!
Tips for Success
CS402: Computer Communications and Networks is a self-paced course, which means that you can decide when you will start and when you will complete the course. There is no instructor or an assigned schedule to follow. We estimate that the "average" student will take 42 hours to complete this course. We recommend that you work through the course at a pace that is comfortable for you and allows you to make regular progress. It's a good idea to also schedule your study time in advance and try as best as you can to stick to that schedule.
Learning new material can be challenging, so we've compiled a few study strategies to help you succeed:
- Take notes on the various terms, practices, and theories that you come across. This can help you put each concept into context, and will create a refresher that you can use as you study later on.
- As you work through the materials, take some time to test yourself on what you remember and how well you understand the concepts. Reflecting on what you've learned is important for your long-term memory, and will make you more likely to retain information over time.
- Although you may work through this course completely independently, you may find it helpful to connect with other Saylor students through the discussion forums. You may access the discussion forums at https://discourse.saylor.org.
This course is delivered entirely online. You will be required to have access to a computer or web-capable mobile device and have consistent access to the internet to either view or download the necessary course resources and to attempt any auto-graded course assessments and the final exam.
- To access the full course including assessments and the final exam, you will need to be logged into your Saylor Academy account and enrolled in the course. If you do not already have an account, you may create one for free here. Although you can access some of the course without logging in to your account, you should log in to maximize your course experience. For example, you cannot take assessments or track your progress unless you are logged in.
- If you plan to attempt the optional Direct Credit final exam, then you will also need access to a webcam. This lets our remote proctoring service verify your identity, which is required to issue an official transcript to schools on your behalf.
For additional guidance, check out Saylor Academy's FAQ.
This course is entirely free to enroll in and to access. Everything linked in the course, including textbooks, videos, webpages, and activities, is available for no charge. This course also contains a free final exam and course completion certificate.
This course also has an optional final exam that can give you an opportunity to earn college credit. This exam requires the use of a proctoring service for identity verification purposes. The cost for proctoring for this optional exam is $5 per session.