week 01 lecture

Telecom SwitchingSpring 2010

Course Introduction Instructor:

Taimoor Shah Credit Hours:

3 Lectures:

2 per week – 1.5 hrs each Lab:

No formal lab

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Telecom Switching, Spring 2010

Introduction

Communication: Email / In-person

Office: In front of Director’s office

Consultation Time: Section A: Thursday 12:30 to 2:00

3Telecom Switching, Spring 2010

Introduction

Medium of Instruction: English

Attendance: University policy (80%)

Pre-requisite: Telecom Systems

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Introduction Textbook:

Data Communications & Networking, by Behrouz Forouzan (3rd or 4th Edition)

Reference Books: Data and Computer Communications, by

William Stallings


Assessment

Quizzes: Five quizzes over the semester 2% each Short (5-10 min) May be announced or unannounced

Assignments: Two assignment projects 5% weight each Research Assignments 6


Assessment Mid-Term Exam:

2 mid-term exams 15% each Week 6 and Week 11 1 Hour exam Covers preceding weeks lectures

Final Exam: 50% marks Covers ALL lectures 3 Hours exam 7


Course Outline

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Course Outline


Lectures Server

Lectures are posted on ‘Lectures’ server

Can be accessed from inside and outside the university

Look for folder “Taimoor Shah > Spring2010 > TelecomSwitching”

Other relevant material, e.g. e-books, assignments, solutions posted too


How to get better grades? You know it


Introduction & Motivation

Week 1

Data Communication

The term telecommunication means communication at a distance.

The word data refers to information presented in whatever form is agreed upon by the parties creating and using the data.

Data communications are the exchange of data between two devices via some form of transmission medium such as a wire cable.


Figure 1.1 Five components of data communication


Characteristics Delivery Accuracy Timeliness Jitter


1.16

Data representation Text Numbers Images Audio video


Fundamental problem

“The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point” - The Mathematical Theory of Communication, Claude Shannon


Contemporary Data Comms trends

traffic growth at a high & steady rate development of new services advances in technology

significant change in requirements emergence of high-speed LANs corporate WAN needs digital electronics


Spectrum for Cloud Computing “Cloud computing can only deliver

the full benefits when there is ubiquitous and affordable broadband access. Continuity of access will encourage consumers to make greater use of cloud computing services and SMEs to focus more on developing new content and services” – Microsoft General Counsil Brad Smith (26th Jan 2010) 19Telecom Switching, Spring 2010

A Communications Model


Telecom Switching, Spring 2010 21

Communications TasksTransmission system utilization Addressing

Interfacing Routing

Signal generation Recovery

Synchronization Message formatting

Exchange management Security

Error detection and correction Network management

Flow control

Data Communications Model


Transmission Medium

selection is a basic choice internal use entirely up to business long-distance links made by carrier

rapid technology advances change mix fiber optic wireless

transmission costs still high hence interest in efficiency

improvements 23Telecom Switching, Spring 2010

Networking growth of number & power of

computers is driving need for interconnection

also seeing rapid integration of voice, data, image & video technologies

two broad categories of communications networks: Local Area Network (LAN) Wide Area Network (WAN)


Wide Area Networks

span a large geographical area cross public rights of way rely in part on common carrier

circuits alternative technologies used

include: circuit switching packet switching frame relay Asynchronous Transfer Mode (ATM) 25Telecom Switching, Spring 2010

Circuit Switching

uses a dedicated communications path established for duration of conversation

comprising a sequence of physical links

with a dedicated logical channel eg. telephone network


Packet Switching

data sent out of sequence small chunks (packets) of data at a

time packets passed from node to node

between source and destination used for terminal to computer and

computer to computer communications


Packet Switching


A Network Switch


Frame Relay

packet switching systems have large overheads to compensate for errors

modern systems are more reliable errors can be caught in end system Frame Relay provides higher speeds with most error control overhead

removed


Asynchronous Transfer Mode ATM evolution of frame relay fixed packet (called cell) length with little overhead for error control anything from 10Mbps to Gbps constant data rate using packet

switching technique with multiple virtual circuits


Local Area Networks

smaller scope Building or small campus

usually owned by same organization as attached devices

data rates much higher switched LANs, eg Ethernet wireless LANs


Metropolitan Area Networks MAN middle ground between LAN and

WAN private or public network high speed large area


The Internet Internet evolved from ARPANET

first operational packet network applied to tactical radio & satellite nets

also had a need for interoperability led to standardized TCP/IP protocols


Internet Elements


Internet Architecture


Example Configuration


Trends in Telecom in 2010 (UK)What will have the biggest impact on

networking and telecoms in 2010? Passing of the Digital Economy Bill Auction of "digital dividend" spectrum More surveillance by the authorities of

who is on the net and what they are doing Increasing congestion on mobile networks

as people switch to smart (ie, mobile networked) devices


Latest trends Lots more investment by mobile and fixed

network operators to boost capacity, speed, reliability and quality of service

Increasing use of mobile and social network technology to reach customers, workers and friends

Growing pressure for homogenity with respect to technology platforms, regulations and prices throughout Europe, and increasingly, the world

Climate change and the need to be green to rise up the agenda for both cost and political reasons


week 01 lecture

Documents