CS402: Computer Communications and Networks

Read this introduction to the basic terms and technologies we will cover in this course, as well as a brief review of how the Internet and computer networks evolved over time.

This video covers the historical significance of the IETF in shaping the Internet. The IETF's origins were as a network working group in the late 1960s, before the Advanced Research Projects Agency Network (ARPANET) implementation. Vint Cerf and Bob Kahn were instrumental in developing TCP/IP and transitioning ARPANET to TCP/IP in 1983. In 1986, the IETF's mission was to address engineering challenges within the DoD Internet, which included ARPANET and the Military Network (MILNET). The Internet Activities Board (IAB) transformed into the Internet Architecture Board (IAB) in 1992, which brought about changes in the roles of the Internet Engineering Steering Group (IESG) and the Internet Research Task Force (IRTF). There was controversy surrounding the IAB's recommendation of IP version 7 (IPv7), which led to the restructuring of the IETF and IAB through the POISED Working Group.

This video discusses Internet-Drafts (I-Ds) and Requests for Comments (RFCs) in the context of the Internet Engineering Task Force (IETF). It explores the unrestricted accessibility of IETF documents and the legal guidelines governing their use and distribution. What are the roles of RFCs as live documents and permanent records? Review the specifics of document formats, translation permissions, and regulations for excerpt publication, and note the file naming conventions, various RFC categories, such as Best Current Practices and Internet Standards, and the emphasis on compatibility over strict adherence in the path to standardization.

This chapter serves as an introduction to networking as you link across time to review the development of standards and technologies that comprise today's wired and wireless information systems entangled in the Web. What is the difference between a service and a protocol? What is topology, and what is a transmission mode? What is the purpose of each?

Watch this video about network topology and the difference between logical and physical topologies. You should become familiar with network structures such as bus, ring, star, mesh, point-to-point, point-to-multipoint, and MPLS. You should be able to recognize and explain these topologies, including their characteristics and some real-world applications.

This video explores the various forms of physical transmission media utilized in communication networks, namely twisted pair cable, coaxial cable, and fiber optic cable. You should be able to distinguish between these media types, their core applications, the materials they are constructed from, and their specific purposes in network communication.

While watching this video, focus on understanding network devices and their functions. How do devices like hubs, repeaters, concentrators, and amplifiers extend data transmission distances within specific network domains? Modems convert digital to analog signals. Bridges facilitate traffic forwarding based on MAC addresses and network connectivity between topologies. Switches reduce collision domains and direct packets using MAC addresses, while advanced switches enhance security and routing capabilities. Routers connect networks and use routing protocols to determine data paths. Network segmentation limits exposure to threats and controls movement within the network.

Layers are the foundation for studying computer networks. You must understand how to work with layers to describe the flow of a data request to its destination and how the reverse occurs when the destination sends a response.

Watch this video on Wide Area Networks (WANs). Common WAN components are copper line drivers, demarcation points, and Network Interface Units (NIUs). WANs are used to connect LANs over long distances. Common WAN issues include Internet connectivity problems, DNS issues, and interface concerns. How these issues can be resolved and troubleshooted?

This section discusses how networked applications are built on top of the transport service. There are two main types of transport services: connectionless and connection-oriented. What are the similarities and differences between the two types of services?

Watch this video from 37:08 to 58:00. Focus on the three common guided media for data transmission: twisted pair, coaxial cable, and optical fiber. Note their key characteristics and applications. Consider the advantages and disadvantages of each medium in terms of data rates and distances they can cover. Think about when it might be more practical to use twisted pair for shorter distances, coaxial cable for medium distances, or optical fiber for long-distance, high-speed connections. Be able to identify the main differences between these media. What are some real-world scenarios where you might choose one over the others?