FIT3165 Lecture Notes - Lecture 6: Data Transmission, High-Level Data Link Control, Data Link Layer
22 Jun 2018
School
Department
Course
Professor
Lecture 6 - Data Link
●The Internet is a combinaon of networks glued together by connecng devices (routers or
switches)
●A datagram travelling from one host to another host needs to pass through these networks
Nodes and Links
Communicaon at the data-link layer is node-to-node
Two Type of Links
Point-to-Point Link
Uses the whole capacity of the medium
Broadcast Link
Uses only part of the capacity of link
Sublayers
Data Link Control (DLC)
Deals with all issues common to both point-to-point and broadcast links
Media Access Control (MAC)
Deals only with issues specific to broadcast links
Data Link Control (DLC)
Deals with procedures for communicaon between two adjacent nodes in the network.
Funcons:
●Framing: how to organise the bits that are carried by the physical layer
●Flow and error control: Techniques for error detecon are discussed at the end of this secon
●Error detecon and correcon
Document Summary
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