Computer communication networks chapter 1 ppt (vtu odd sem EC)

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Computer Communication Networks

Mr. Kunjan D Shinde

Assistant ProfessorDepartment of Electronics and Communication Engineering

PESITM Shivamogga.

213/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

UNIT 1Network ModelsLayered TaskOSI ModelWorking of

Physical layer, Data link layer, Network layerTransport layer, Session layer, Presentation layerApplication layer

TCP/IP Protocol SuiteWorking of each layers

AddressingPhysical, Logical, Port, and Specific addressing. Acall Last_Class

Telephone and Cable Networks for Data CommunicationTelephone NetworksDial up modemDSLCable TV for data Transmission

Computer Communication Networks

Contents Chapter 1

313/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Layered Task

Computer Communication Networks

Chapter 1: Network Models

413/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Seven Layers of OSI model

ISO- International Standards Organization. - International Organization for Standardization.

- Established in 1947- Multifunctional body dedicated to worldwide

agreement on international standards.- ISO standard that covers all aspect of Network

Communication is OSI model

OSI – Open System Interconnect Model- 1st introduced in late 1970’s- has 7 ordered layers- Open System is set of protocols that allows two

different system to communicate regardless of their underlying hardware or software

- OSI is not a protocol- purpose is to facilitate communication b/w different

systems without changing its logic of underlying h/w and s/w.

ISO is Organization. OSI is the Model

513/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

The Interaction Between layers in the OSI Model

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Computer Communication Networks

Chapter 1: Network Models

An exchange of data using the OSI model

713/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Physical Layer

Functions of Physical layerPhysical Layer is responsible for movements of individual bits from one hop(node) to the

next.- Physical Characteristics - Data Rate- Synchronization of Bits- Line Configuration- Physical Topology- Transmission Mode

813/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Data Link Layer

Functions of Data Link layerData Link Layer is responsible for moving frames from one hop(node) to the next.

- Framing- Physical Addressing- Flow control- Error Control- Access Control

913/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Hop to Hop Delivery

1013/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Network Layer

Functions of Network layerNetwork Layer is responsible for the delivery of individual packets from source to

destination.

- Logical Addressing- Routing

1113/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Source to destination Delivery

1213/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Transport Layer

Functions of Transport layerTransport Layer is responsible for the delivery of the message from one process to another.

- Service point addressing- Segmentation and Reassembly- Connection control- Flow control- Error control

1313/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Reliable Process to process delivery

1413/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Session Layer

Functions of Session layerSession Layer is responsible for dialog control and synchronization.

- Dialog control- Synchronization

1513/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Presentation Layer

Functions of Presentation layerPresentation Layer is responsible for Translation, compression and encryption.

- Translation- Encryption- Compression

1613/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Application Layer

Functions of Application layerApplication Layer is responsible for providing services to the user.

- Network Virtual terminal- File transfer, access, and management- Mail services- Directory Services

1713/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Summary of Layers in OSI model

1813/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

TCP/IP Protocol Suite

1913/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Addressing

2013/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Physical Addressing

07:01:02:01:2C:4B

A 6-byte (12 hexadecimal digits) physical address.

2113/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Logical Addressing

2213/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Port Addressing

2313/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Port Addressing

753

A 16-bit port address represented as one single number.

2413/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Specific Addressing

Specific address is used in some applications which need user friendly addresses.

Example

email: kunjanshinde@pestrust.edu.in- used to define the address of the receiver.

URL- Universal Resource LocatorURL- www.pestrust.edu.in/pesitm/

-used to find a document on World Wide Web

2513/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

The telephone network had its beginnings in the late 1800s and was originally created to provide voice communication.

Need to communicate digital data results in the invention of the dial-up modem

High speed downloading – DSL- Digital Subscriber Line

The entire network, which is referred to as the plain old telephone system (POTS), was originally an analog system using analog signals to transmit voice.

PSTN : Public Switched Telephone Networks

Telephone networks use circuit switching.

2613/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Endoffices

Local loop

Trunk

Tandemoffices Regional offices

Trunk

• • •

It has 3 major components 1. Local Loops – Twisted pair cable, END/local central office, BW- 4kHz for voice

083622229542. Trunks – is a transmission media handles Communication b/w offices

3. Switching Offices - to avoid physical link b/w two subscriber, Telephone company has switches.

- A switch connects several local loops or trunks and allows a connection b/w different subscribers.

Major Components of Telephone Networks

2713/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Unit 1

Home workStudy and prepare notes on

1. LATA1. Intra LATA Service2. Inter LATA Service

Point of Presence2. Signaling 1. Study in detail 2. Data Transfer Network and Signaling Network 3. Signaling System Seven (SS7)

Detailed notes on Layers in SS73. Services Provided by telephone Network4. Dial up modem – basic, v.32, v.34, v.90 and v.92

Last Date for Submission : its up to u.. Set a date

3313/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Telephone companies developed a new technology when the traditional modems reached their peak data rate, this new technology was DSL- Digital Subscriber Line.

DSL is used to provide higher-speed access to the Internet.

Digital subscriber line (DSL) technology is one of the most promising for supporting high-speed digital communication over the existing local loops.

Variants of DSL are

ADSL -AsymmetricHDSL -High bit rateSDSL -SymmetricVDSL -Very high bit rate xDSL - generally referred as xDSL where x = A, H, S, or V.

Digital Subscriber Line

3413/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Some points on ADSL

ADSL- Asymmetric –b’coz it uses a different speed in upstream and downstream.- downstream has higher data rate than upstream

ADSL is an asymmetric communication technology designed for residential users; it is not suitable for businesses.

The existing local loops can handle bandwidths up to 1.1 MHz (data and voice Communication).

ADSL is an adaptive technology. The system uses a data rate based on the condition of the local loop line.

1. Using Existing Local Loops-uses a existing local loops.-new BW was achieved by ADSL, b’coz of change in the filter used by

TC.

3513/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Some points on ADSL Cont’d..

2. Adaptive Technology-1.1 MHz is a theoretical bandwidth of Local Loops.- some factors that influence the change in BW property are Distance, Size of the cable, Signaling used and so .on..- Hence these factors need to be taken care, so the Adaptive Technology.Adaptive technology is used to test the conditions of the channel and to find the available BW of the line- Data rate of the ADSL is not fixed, it changes based on the condition and type of local loop cable.

3. Discrete multitone Technique (DMT)-Modulation Technique used by ADSL is DMT.-No predefine way to set the BW and divide among the users (each s/m can decide on its BW division).- typical BW -1.104MHz is divided in to 256 channels.-each channel uses the BW of 4.312kHz

3613/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Discrete Multitone technique

3713/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Bandwidth Division in ADSL

-Voice - Channel 0- Idle - Channel 1 to 5- Upstream data and Control -Channel 6 to 30 (24 channels), QAM modulation is used and BW is 24*4000*15=1.44Mbps {normal 500kbps b’coz of noise} - Downstream Data and Control - Channel 31 to 255 (24 channels), QAM modulation is used and BW is 224*4000*15=13.4Mbps{normal 8Mbps b’coz of noise}

3813/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

3913/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

High-bit-rate digital subscriber line (HDSL): It’s an alternative to T-1 line(1.544 Mbps)

Limitation of T-1 line is it uses alternative mark inversion(AMI) encoding, which is very susceptible to attenuation at high frequencies. Thus the length of T-1 line is limited to 3200ft (1km). Thus there is need of repeater for longer distances.

HDSL uses 2B1Q encoding which is less susceptible to attenuation. Up to a distance of 12000ft(3.86km) a data rate of 1.544Mbps can be achieved without repeaters.

HDSL uses 2 twisted pairs (One pair for each direction) to achieve full-duplex transmission.

4013/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Summary

4113/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

The cable TV network started as a video service provider, but it has moved to the business of Internet access. In this section, we discuss cable TV networks per se; in Section 9.5 we discuss how this network can be used to provide high-speed access to the Internet.

4213/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Communication in the traditional cable TV network is unidirectional.

4313/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Communication in an HFC cable TV network can be bidirectional.

4413/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Cable companies are now competing with telephone companies for the residential customer who wants high-speed data transfer. In this section, we briefly discuss this technology.

BandwidthSharingCM and CMTSData Transmission Schemes: DOCSIS

4513/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

Downstream data are modulated using the 64-QAM modulation technique.

The theoretical downstream data rateis 30 Mbps. The theoretical upstream data rate

is 12 Mbps.

Upstream data are modulated using the QPSK modulation technique.

4613/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

4713/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Telephone Networks

4813/08/2015 Mr. Kunjan D. Shinde, Asst. Professor, Dept. of E&CE, PESITM Shivamogga.

Computer Communication Networks

Chapter 1: Network Models

Thank u

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