Transcript Main presentation title goes here.

Wireless and Mobile
Networks
(ELEC6219)
Session 1: Introduction to the Module
Adriana Wilde and Jeff Reeve
22 January 2015
Plan for this lecture
• At the end of this lecture (and related activities), students
should be able to demonstrate knowledge and
understanding of:
– Module overview and expectations
– Network architecture and model
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Housekeeping
and General
Information
Housekeeping
• Make sure you know :
– Where are the toilets/bottle vending machines
– What to do in the event of fire
• (My) Ground Rules:
– If too fast / can’t understand – stop me!
– Questions OK at any time
– Attend lectures!
– Be punctual
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Who are we?
• Jeff Reeve, [email protected]
(6 weeks of lectures)
B59/4233
jsr
• Professor Lie-Liang Yang, [email protected]
agw106
Unit Leader
(6 weeks)
B53/4006
lly
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Whilst I've got your attention...
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What will we cover?
• Jeff Reeve, [email protected]
(6 weeks of lectures)
B59/4233
Basic network theory
• Professor Lie-Liang Yang, [email protected]
Unit Leader
(6 weeks)
B53/4006
Wireless and mobile theory
agw106
jsr
lly
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What will we cover? (II)
• Jeff Reeve, [email protected]
(3 weeks of lectures)
B59/4233
jsr
– Network Layer and Routing
– ARP, Transport Layer
– Congestion Control, etc
– TCP - Applications
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What will we cover? (III)
– Cellular Wireless Networks,
– Wireless LANs
– Wireless Sensor Networks
• Professor Lie-Liang Yang, [email protected]
Unit Leader
(6 weeks)
B53/4006
lly
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When/Where?
• Lectures:
– Wednesdays 9:00 – 9:45
Building 54 / Room 5027
– Thursdays 13:00 – 13:45
Building 46 / Room 2003
• Weeks 1-11, 15
B46 ©2010 François-Xavier Beckers (CC-BY)
– Monday 01 October 2012 - Saturday 13 January 2013
– Christmas break: 17 December - 06 January
(no lectures)
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Examination
• This module is assessed 100% by examination
• Duration: 120 minutes
• Two sections:
– Section A: Two questions, set by jsr
– Section B: Three questions, set by lly
• Answer three questions:
– At least 1 from each section
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Module Context
• Knowledge expected
– Algorithms and Programming
– Computer Architecture fundamentals
– Operating Systems fundamentals
• Not a pre-requisite:
– Computer Networks
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Talking point
• What do you know already about networking?
<brainstorm>
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Network
Architecture and
Models
Motivation
• How do we transfer data on computer networks?
• Networking...
– … is complex
We need to break the task up, using a layered model
– ... involves communication
We need to understand the principles of communication
– … is done for real
p.37-49 (Tanenbaum 4th ed)
p.63-76 (Tanenbaum 5th ed)
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Network architecture and Model
TCP/IP – Transmission Control Protocol over Internet Protocol
Extremely important! (Basis of the Internet)
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TCP/IP architecture and Model
p.26-30 (T. 4ed)
p.51-55 (T. 5ed)
• The software running on Host 1 runs in the application
layer, and communicates via protocols to its peer in Host 2:
•
Each protocol instance
talks virtually to its peer
•
Each layer
communicates only by
using the one below
•
Lower layer services
are accessed by an
interface
•
At bottom, messages
are carried by the
medium
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The ISO/OSI Model
• International Standards Organisation (Open Systems
Interconnection)
– Provides functions needed by users
– Converts different representations
– Manages task dialogs
– Provides end-to-end delivery
– Sends packets over multiple links
– Sends frames of information
– Sends bits as signals
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The ISO/OSI Model
In ALL textbooks – but
can be safely ignored!
• International Standards Organisation (Open Systems
Interconnection)
– Provides functions needed by users
– Converts different representations
– Manages task dialogs
– Provides end-to-end delivery
– Sends packets over multiple links
– Sends frames of information
– Sends bits as signals
These layers are “more-or-less” accepted
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The ISO/OSI Model
• International Standards Organisation (Open Systems
Interconnection)
DEAD!
Reasons?
TCP/IP does not map well onto it
LANs do not map well onto it
p.46 (Tanenbaum 4th ed)
p.73 (Tanenbaum 5th ed)
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Network architecture and Model
• The Tanenbaum's hybrid model is the one we adopt for this
module
• TCP/UDP
IP
Ad-hoc
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Data
Communications
Fundamentals
Data Communications Fundamentals
• We wish to communicate from A to B.
– How?
A
B
– By courier (e.g. magnetic media), optically (light and
fiber optics), electrically, electromagnetic waves, radio,
microwaves, satellite… many alternatives!
p.91 (Tanenbaum 4th ed)
p.116 (Tanenbaum 5th ed)
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How?
• Electrical options:
– vary the voltage (the most important mechanism)
– vary the current (sometimes used in ‘noisy’
environments)
– vary the frequency (e.g. dial-up modems)
– vary the phase
• EM wave options:
– open space “wireless”
• … many alternatives!
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Checking Learning Outcomes
• At the end of this lecture (and related activities), students
should be able to demonstrate knowledge and
understanding of:
– Module overview and expectations
– Network architecture and models
• I'll see you tomorrow at 13:00 in B46/2003
– Please get your copy of the Tanenbaum now and read
the selected pages
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