• Unit 5: The Network Layer

    In this unit, we will learn how packets (groupings of data) travel on a network and how each machine can be addressed uniquely so that data transport between two nodes is reliable. We will learn that networks can run out of space, meaning that unique addresses for different machines are no longer available. In these situations, computer scientists must manage IP addressing using CIDR and subnetting – techniques we will learn about in this unit.

    The network layer is responsible for the delivery of packets from any source to any destination through intermediate routers. Follow the links to explore in detail the IPv4, IPv6, RIP, OSPF, and BGP protocols used in today's Internet.

    Completing this unit should take you approximately 11 hours.

    • 5.1: Principles

      • 5.1.1: Organization of the Network Layer

      • 5.1.2: The Control Plane

        • 5.1.2.1: Static Routing

        • 5.1.2.2: Distance Vector Routing

        • 5.1.2.3: Link State Routing

    • 5.2: Internet Protocol

      • 5.2.1: IP version 4 (IPv4)

      • 5.2.2: Internet Control Message Protocol (ICMP) Version 4

      • 5.2.3: IP version 6 (IPv6)

      • 5.2.4: ICMP Version 6 (ICMPv6)

      • 5.2.5: Middleboxes

      • 5.2.6: Network Address Translation (NAT)

    • 5.3: Routing in IP Networks

      • 5.3.1: Intradomain Routing

        • 5.3.1.1: Routing Information Protocol (RIP)

        • 5.3.1.2: Open Shortest Path First (OSPF)

      • 5.3.2: Interdomain Routing

    • 5.4: Practice Exercises

    • Unit 5 Assessment