Wireless and Mobile Networks (ELEC6219) Session 1: Introduction to the Module

Adriana Wilde and Jeff Reeve22 January 2015

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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

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, jsr@ecs.soton.ac.uk

(6 weeks of lectures)B59/4233

• Professor Lie-Liang Yang, lly@ecs.soton.ac.uk Unit Leader (6 weeks)B53/4006

agw106

jsr

lly

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Whilst I've got your attention...

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What will we cover?

•Jeff Reeve, jsr@ecs.soton.ac.uk (6 weeks of lectures)B59/4233

•Professor Lie-Liang Yang, lly@ecs.soton.ac.uk Unit Leader (6 weeks)B53/4006

agw106

jsr

lly

Wireless and mobile theory

Basic network theory

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What will we cover? (II)

• Jeff Reeve, jsr@ecs.soton.ac.uk (3 weeks of lectures)B59/4233

– Network Layer and Routing

– ARP, Transport Layer

– Congestion Control, etc

– TCP - Applications

jsr

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What will we cover? (III)

– Cellular Wireless Networks,

– Wireless LANs

– Wireless Sensor Networks

• Professor Lie-Liang Yang, lly@ecs.soton.ac.uk Unit Leader (6 weeks)B53/4006

lly

When/Where?• Lectures:

– Wednesdays 9:00 – 9:45Building 54 / Room 5027

– Thursdays 13:00 – 13:45Building 46 / Room 2003

• Weeks 1-11, 15

– Monday 01 October 2012 - Saturday 13 January 2013

– Christmas break: 17 December - 06 January (no lectures)

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B46 ©2010 François-Xavier Beckers (CC-BY)

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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>

Network Architecture and Models

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Motivation• How do we transfer data on computer networks?

• Networking...

– … is complexWe need to break the task up, using a layered model

– ... involves communication We need to understand the principles of communication

– … is done for realp.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• 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

p.26-30 (T. 4ed)p.51-55 (T. 5ed)

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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• 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 signalsThese layers are “more-or-less” accepted

In ALL textbooks – but can be safely ignored!

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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/UDPIPAd-hoc

Data Communications Fundamentals

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Data Communications Fundamentals• We wish to communicate from A to B.

– How?

– By courier (e.g. magnetic media), optically (light and fiber optics), electrically, electromagnetic waves, radio, microwaves, satellite… many alternatives!

A B

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