Lecture 20: Link Layer; Ethernet
The link layer provides transport-like services between connected hosts. This lecture will examine the link layer in a general way, followed by a close look at Ethernet. Ethernet is quite an interesting link layer technology and has been extraordinarily successful in wiring the world together. The shared-medium concept is a great strength as well as some trouble interms of media access.
Lesson Objectives
By the end of this lesson, the student will be able to:
- describe the mission, scope, addressing mechanism, data types and responsibilities/services of the Data Link Layer.
- describe the differences between broadcast and point-to-point links.
- describe three different general types of media access protocols.
- describe the CSMA/CD protocol, including the details of Ethernet's implementation.
- use space-time diagrams to describe or solve problems relating to media access, including details of Ethernet's implementation.
- describe the Ethernet frame format.
- solve problems involving interaction of several Ethernet senders and receivers, collisions, propagation times, and the details of Ethernet's CSMA/CD algorithm.
Reading
- KR Ch 6.1
- KR Ch 6.2 - 6.3 (skim)
- KR Ch 6.4.1 - 6.4.2