introduction to network architecture

8/9/2019 Introduction to Network Architecture

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Slide 1

Introduction

Chapter 1

Monday Sept 8th, 2008


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Slide 2

Uses of Computer Networks

Business Applications

Home Applications

Mobile Users Social Issues


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Slide 3

Business Applications of Networks

A network with two clients and one server.


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Slide 4

Business Applications of Networks (2)

The client-server model involves requests and replies.


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Slide 5

Home Network Applications

Access to remote information

Person-to-person communication

Interactive entertainment

Electronic commerce


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Slide 6

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers.


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Slide 7

Home Network Applications (3)

Some forms of e-commerce.


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Slide 8

Mobile Network Users

Combinations of wireless networks and mobile computing.


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Slide 9

Network Hardware

Local Area Networks (LAN)

Metropolitan Area Networks (MAN)

Wide Area Networks (WAN) Wireless Networks

Home Networks

Internetworks

Wednesday Sept 10th, 2008


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Slide 10

Broadcast Networks

Types of transmission technology

Broadcast links Broadcast : send to everyone

Multicast : send to a set of nodes

Point-to-point links


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Slide 11

Broadcast Networks (2)

Classification of interconnected processors by scale.


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Slide 12

Local Area Networks

Two broadcast networks

(a) Bus (e.g. Ethernet - IEEE 802.3)

(b) Ring


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Slide 13

Metropolitan Area Networks

A metropolitan area network based on cable TV.

Another example : (Wimax IEEE 802.16)


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Slide 14

Wide Area Networks

Relation between hosts on LANs and the subnet.


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Slide 15

Wide Area Networks (2)

A stream of packets from sender to receiver.


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Slide 16

Wireless Networks

Categories of wireless networks:

System interconnection (e.g.

Bluetooth)

Wireless LANs (e.g. Wifi)

Wireless WANs (e.g. Mobilephone, Wimax)


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Slide 17

Wireless Networks (2)

(a) Bluetooth configuration

(b) Wireless LAN


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Slide 18

Wireless Networks (3)

(a) Individual mobile computers

(b) A flying LAN


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Slide 19

Home Network Categories

Computers (desktop PC, PDA, shared peripherals

Entertainment (TV, DVD, VCR, camera, stereo, MP3)

Telecomm (telephone, cell phone, intercom, fax)

Appliances (microwave, fridge, clock, furnace, airco) Telemetry (utility meter, burglar alarm, babycam).


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Slide 20

Network Software

Protocol Hierarchies

Design Issues for the Layers

Connection-Oriented and Connectionless Services

Service Primitives The Relationship of Services to Protocols

Monday Sept 15th, 2008


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Slide 21

Network SoftwareProtocol Hierarchies

Layers, protocols, and interfaces.

Protocol : agreement between two parties

(peers) on how communication is to proceed


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Slide 22

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture.


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Slide 23

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5.

M : message

H : Head

T : Tail


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Slide 24

Design Issues for the Layers

Addressing (to whom)

Error Control (error in message content)

Flow Control (transmitted too fast) Multiplexing (sharing the wire)

Routing (changing from one network to another)


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Slide 25

Connection-Oriented and Connectionless

Services

Six different types of service.

Before communication,

set up configuration

e.g. mobile communication

No set up before

communication,

e.g. SMS

Service : a communication functionprovided by a layer to the upper layer


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Slide 26

Service Primitives

Five service primitives for implementing a simple connection-

oriented service.


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Slide 27

Service Primitives (2)

Packets sent in a simple client-server interaction on a

connection-oriented network.


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Slide 28

Services to Protocols Relationship

The relationship between a service and a protocol.

Service vs Protocol

Communication Service : set of primitives at the interface level

Protocol : set of rules on message format and meaning


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Slide 29

Reference Models

The OSI Reference Model Open Systems Interconnection

The TCP/IP Reference Model

A Comparison of OSI and TCP/IP

A Critique of the OSI Model and Protocols

A Critique of the TCP/IP Reference Model

Monday Sept 22nd, 2008


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Slide 30

Reference Models

The OSI

referencemodel.

PDU :

Protocol Data Unit


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Slide 31

Reference Layer

Layer 1 (Physical layer) : transmit 1,0 over a physical signal (electric, voltage,

noise, )

Layer 2 (Data link layer) : transmit a sequence of bits called Frame. The size of a

frame is limited. Error transmission is handled there. Ack support

When broadcast network (ethernet) than handles network access

Layer 3 (Network layer) : transmission over other physical networks. Routing

function. Congestion (Flow control)

Layer 4 (Transport layer) : Message of any length. Overall communication service.


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Slide 32

Reference Models (2)

The TCP/IP reference model.


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Slide 33

Reference Models (3)

Protocols and networks in the TCP/IP model initially.


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Slide 34

Comparing OSI and TCP/IP Models

Concepts central to the OSI model

Services

Interfaces

Protocols


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Slide 35

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

Bad timing

Bad technology Bad implementations

Bad politics


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Slide 36

Bad Timing

The apocalypse of the two elephants.


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Slide 37

A Critique of the TCP/IP Reference Model

Problems: Service, interface, and protocol not distinguished

Not a general model

Host-to-network layer not really a layer No mention of physical and data link layers

Minor protocols deeply entrenched, hard to replace


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Slide 38

Hybrid Model

The hybrid reference model to be used in this book.


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Slide 39

Example Networks

The Internet

Connection-Oriented Networks:

X.25, Frame Relay, and ATM

Ethernet

Wireless LANs: 802:11


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Slide 40

The ARPANET

(a) Structure of the telephone system.

(b) Barans proposed distributed switching system.

1970s

TCP/IP 1974


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Slide 41

The ARPANET (2)

The original ARPANET design.


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Slide 42

The ARPANET (3)

Growth of the ARPANET (a) December 1969. (b) July 1970.

(c) March 1971. (d) April 1972. (e) September 1972.


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Slide 43

NSFNET

The NSFNET backbone in 1988.


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Slide 44

Internet Usage

Traditional applications (1970 1990)

E-mail

News Remote login

File transfer


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Slide 45

Architecture of the Internet

Overview of the Internet.


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Slide 46

ATM Virtual Circuits

A virtual circuit.

Wednesday Sept 25th, 2008


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Slide 47

ATM Virtual Circuits (2)

An ATM cell (i.e. packet).


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Slide 48

The ATM Reference Model

The ATM reference model.


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Slide 49

The ATM Reference Model (2)

The ATM layers and sublayers and their functions.

h


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Slide 50

Ethernet

Architecture of the original Ethernet.

i l A


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Slide 51

Wireless LANs

(a) Wireless networking with a base station.

(b) Ad hoc networking.

Wi l LAN (2)


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Slide 52

Wireless LANs (2)

The range of a single radio may not cover the entire system.

Wi l LAN (3)


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Slide 53

Wireless LANs (3)

A multicell 802.11 network.

N k S d di i


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Slide 54

Network Standardization

Whos Who in the Telecommunications World

Whos Who in the International Standards World

Whos Who in the Internet Standards World

ITU


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Slide 55

ITU

Main sectors Radiocommunications

Telecommunications Standardization

Development

Classes of Members

National governments

Sector members Associate members

Regulatory agencies

IEEE 802 Standards


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Slide 56

IEEE 802 Standards

The 802 working groups. The important ones are

marked with *. The ones marked with are

hibernating. The one marked with gave up.

M t i U it


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Slide 57

Metric Units

The principal metric prefixes.

introduction to network architecture

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