Lectures and handouts by: Brian Friedrich, MEd, CGA, FCCA(UK) Laura Friedrich, MSc, CGA, FCCA(UK)
2010-11
Module 8 - Table of Contents
Part 1 2 3 4 5 6 Content Overview of telecommunications and Network basics (8.1 & 8.3) Strategic uses of telecommunications and trends in network management (8.2 & 8.4) Network security issues (8.5) Planning and managing wireless networks (8.6) Remote computing management issues (8.7) Assignment 3 tips
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Part 1 - Overview of telecommunications and Network basics (8.1 & 8.3)
Seven basic communications model elements: • Sender and Receiver • Encoder and Decoder • Channel • Message and Noise
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Part 1 - Overview of telecommunications and Network basics (8.1 & 8.3)
Compare the different channels used in telecommunications networks (Level 1). Two types of signals: • Digital - streams of 0s and 1s – Electrical pulses – Computer data • Analog - continuous waves – Voice – Traditional cable television
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Part 1 - Overview of telecommunications and Network basics (8.1 & 8.3)
The functions of a modem • Modulation - converting digital signal to analog (e.g., to send message from computer across network to Internet) Demodulation - converting analog signal to digital (e.g., to receive message from Internet across network to computer)
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Part 1 - Overview of telecommunications and Network basics (8.1 & 8.3)
Telecommunications channels can be divided into two groups: 1. Wired (conducted) – Twisted pair - e.g., telephone wire, Ethernet – – – Coaxial cable - e.g., television cable Fibre optic USB, FireWire
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Part 1 - Overview of telecommunications and Network basics (8.1 & 8.3)
2. Wireless (radiated) – Different functions naturally occupy, or are assigned, different ranges within the electromagnetic spectrum – AM/FM radio – Microwave – Satellite relay –