Wireless and Mobile Networks (ELEC6219) Session 1: Introduction to the Module Adriana Wilde and Jeff Reeve 22 January 2015

2 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 4

5 Who are we? Jeff Reeve, (6 weeks of lectures) Professor Lie-Liang Yang, Unit Leader (6 weeks) agw106 jsr lly

6 Whilst I've got your attention...

7 What will we cover? Jeff Reeve, (6 weeks of lectures) Professor Lie-Liang Yang, Unit Leader (6 weeks) agw106 jsr lly Wireless and mobile theory Basic network theory

8 What will we cover? (II) Jeff Reeve, (3 weeks of lectures) –Network Layer and Routing –ARP, Transport Layer –Congestion Control, etc –TCP - Applications jsr

9 What will we cover? (III) –Cellular Wireless Networks, –Wireless LANs –Wireless Sensor Networks Professor Lie-Liang Yang, Unit Leader (6 weeks) lly

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 –Monday 01 October Saturday 13 January 2013 –Christmas break: 17 December - 06 January (no lectures) 10 B46 ©2010 François-Xavier Beckers (CC-BY)

11 Examination This module is assessed 100% by examination Duration: 120 minutes Two sections: –Section A: Two questions, set by jsrjsr –Section B: Three questions, set by llylly Answer three questions: –At least 1 from each section

12 Module Context Knowledge expected –Algorithms and Programming –Computer Architecture fundamentals –Operating Systems fundamentals Not a pre-requisite: –Computer Networks

13 Talking point What do you know already about networking?

Network Architecture and Models

15 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 (Tanenbaum 4th ed) p (Tanenbaum 5th ed)

16 Network architecture and Model TCP/IP – Transmission Control Protocol over Internet Protocol Extremely important! (Basis of the Internet)

17 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 (T. 4ed) p (T. 5ed)

18 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

19 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 These layers are “more-or-less” accepted In ALL textbooks – but can be safely ignored!

20 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)

21 Network architecture and Model The Tanenbaum's hybrid model is the one we adopt for this module TCP/UDP IP Ad-hoc

Data Communications Fundamentals

23 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)

24 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!

25 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