unit-vi wireless and broadband network

7/31/2019 Unit-VI Wireless and Broadband Network

1/50

Wireless and BroadbandNetwork

Unit-VI


2/50

RVK 2

Wireless networks

Access computing/communication services, on the move

Cellular Networks traditional base station infrastructure systems

Wireless LANs infrastructure as well as ad-hoc networks possible

very flexible within the reception area

low bandwidth compared to wired networks (1-10 Mbit/s)

Multihop Ad hoc Networks useful when infrastructure not available, impractical, or expensive

military applications, rescue, home networking


3/50


4/50

RVK 4

Evolution of cellular networks First-generation: Analog cellular systems (450-900 MHz)

Frequency shift keying; FDMA for spectrum sharing NMT (Europe), AMPS (US)

Second-generation: Digital cellular systems (900, 1800 MHz) TDMA/CDMA for spectrum sharing; Circuit switching

GSM (Europe), IS-136 (US), PDC (Japan)


5/50

RVK 5

Wireless LANs

Infrared (IrDA) or radio links (Wavelan)

Advantages

very flexible within the reception area

Ad-hoc networks possible (almost) no wiring difficulties

Disadvantages

low bandwidth compared to wired networks

many proprietary solutions Bluetooth, HiperLAN and IEEE 802.11


6/50

RVK 6

Wireless LANs vs. Wired LANs Destination address does not equal destination

location

The media impact the design

wireless LANs intended to cover reasonable

geographic distances must be built from basiccoverage blocks

Impact of handling mobile (and portable) stations Propagation effects

Mobility management

Power management


7/50

Wireless LAN Protocols

A wireless LAN. (a) A transmitting. (b) B transmitting.

7RVK


8/50

Wireless LAN Protocols (2)

The MACA protocol. (a) A sending an RTS to B.

(b) B responding with a CTS to A.

8RVK


9/50

Wireless LANs

The 802.11 Protocol Stack

The 802.11 Physical Layer

The 802.11 MAC Sublayer Protocol The 802.11 Frame Structure

Services

9RVK


10/50


Part of the 802.11 protocol stack.

10RVK


11/50

The 802.11 MAC Sublayer Protocol

(a) The hidden station problem.

(b) The exposed station problem. 11RVK


12/50

The 802.11 MAC Sublayer Protocol (2)

The use of virtual channel sensing using CSMA/CA.

12RVK


13/50


A fragment burst.

13RVK


14/50


Interframe spacing in 802.11.

14RVK


15/50

The 802.11 Frame Structure

The 802.11 data frame.

15RVK


16/50

802.11 Services

Association

Disassociation

Reassociation

Distribution

Integration

Distribution Services

16RVK


17/50

802.11 Services

Authentication

Deauthentication

Privacy

Data Delivery

Intracell Services

17RVK


18/50

Broadband Wireless

Comparison of 802.11 and 802.16





18RVK


19/50


The 802.16 Protocol Stack.

19RVK


20/50


The 802.16 transmission environment.

20RVK


21/50

The 802.16 Physical Layer (2)

Frames and time slots for time division duplexing.

21RVK


22/50


Service Classes

Constant bit rate service

Real-time variable bit rate service

Non-real-time variable bit rate service

Best efforts service

22RVK


23/50


(a) A generic frame. (b) A bandwidth request frame.

23RVK


24/50

Bluetooth

Bluetooth Introduction

Bluetooth Architecture

Bluetooth Applications

The Bluetooth Protocol Stack

The Bluetooth Radio Layer

The Bluetooth Baseband Layer The Bluetooth L2CAP Layer

The Bluetooth Frame Structure

24RVK

l h d i


25/50

Bluetooth Introduction Bluetooth is a new standard developed by a group of electronics

manufacturers that will allow any sort of electronic equipment --

from computers and cell phones to keyboards and headphones --to make its own connections, without wires, cables or any directaction from a user.

Present wireless technology like infra reddata communication has

two problems1)Line of Sight

2) One to One

Usingdata synchronizinge.g. hot syn on a PDA --- problem of

using the right cradle and cable.

Bluetooth overcomes these problems

A key difference with other existing wireless technologies is that

Bluetooth enables combined usability models based on functions

provided by different devices.

25RVK

Bl t th I t d ti (2)


26/50

Bluetooth Introduction (2) The Bluetooth Special Interest Group comprises more than 1000

companies. The major companies who created the technology

include Intel

3 com

Ericcson

IBM

Motorola

Nokia

Toshiba

The name is attributed to Harald Bluetooth was king of Denmark

around the turn of the last millennium. Choosing this name for the standard indicates how important

companies from the Baltic region (nations including Denmark,

Sweden, Norway and Finland) are to the communications

industry 26RVK



27/50

Bluetooth Introduction (3) It provides agreement at the physical level -- Bluetooth is

a radio-frequency standard.

Provides agreement at the data link level where productshave to agree on when bits are sent

how many will be sent at a time

how the parties in a conversation can be sure that the messagereceived is the same as the message sent

Bluetooth is a standard for a small , cheap radio chip to beplugged into computers, printers, mobile phones, etc

Bluetooth chip is designed to replace cables.

27RVK



28/50

Bluetooth Introduction (4)

Information normally carried by the cable, is transmitted

at a special frequency to a receiver Bluetooth chip. These devices can form a quick ad-hoc secure piconet

and start communication.

Connections in the piconetscan occur even when

mobile. A collection of devices connected via Bluetooth technology in

an ad hoc fashion.

Apiconet starts with two connected devices, and may grow toeight connected devices.

All Bluetooth devices are peer units and have identicalimplementations. However, when establishing a piconet, oneunit will act as aMaster and the other(s) asslave(s) for theduration of the piconet connection.

28RVK



29/50

Bluetooth Introduction (5)

Requirements:

Low cost as cableschip $5

Secure as cablesmust support authentication and encryption

Must support both data and voice.

Must connect to a variety of devices.

Must be able to function in a noisy environment.

Data rates721kbps , using the 2.45Ghz radio frequency bandI.S.M (Industrial, scientific and medical)

Must support many simultaneous and private piconets.

Must be low power, compact and global.

29RVK


30/50

Bluetooth Architecture

Two piconets can be connected to form a scatternet.

30RVK


31/50

Bluetooth Applications

The Bluetooth profiles.

31RVK


32/50


33/50

The Bluetooth Frame Structure

A typical Bluetooth data frame.

33RVK


34/50

ATM Virtual Circuits

a) A virtual circuit.

34RVK


35/50

ATM Virtual Circuits (2)

a) An ATM cell.

35RVK


36/50

The ATM Reference Model

a) The ATM reference model.

36RVK


37/50

The ATM Reference Model (2)

a) The ATM layers and sublayers and their functions.

37RVK


38/50

Ethernet

Ethernet Cabling Manchester Encoding

The Ethernet MAC Sublayer Protocol

The Binary Exponential Backoff Algorithm

Ethernet Performance

Switched Ethernet

Fast Ethernet

Gigabit Ethernet IEEE 802.2: Logical Link Control

Retrospective on Ethernet

38RVK


39/50

Ethernet Cabling

The most common kinds of Ethernet cabling.

39RVK


40/50

Ethernet Cabling (2)

Three kinds of Ethernet cabling.

(a) 10Base5, (b) 10Base2, (c) 10Base-T. 40RVK


41/50


Cable topologies. (a) Linear, (b) Spine, (c) Tree, (d) Segmented.

41RVK


42/50


(a) Binary encoding, (b) Manchester encoding,

(c) Differential Manchester encoding.42RVK


43/50

Ethernet MAC Sublayer Protocol

Frame formats. (a) DIX Ethernet, (b) IEEE 802.3.

43RVK


44/50

Ethernet MAC Sublayer Protocol (2)

Collision detection can take as long as 2 .

44RVK


45/50

Ethernet Performance

Efficiency of Ethernet at 10 Mbps with 512-bit slot times.

45RVK


46/50

Switched Ethernet

A simple example of switched Ethernet.

46RVK


47/50

Fast Ethernet

The original fast Ethernet cabling.

47RVK


48/50

Gigabit Ethernet

(a) A two-station Ethernet. (b) A multistation Ethernet.

48RVK

Gi bi h (2)


49/50

Gigabit Ethernet (2)

Gigabit Ethernet cabling.

49RVK

IEEE 802 Standards


50/50

IEEE 802 Standards

The 802 working groups. The important ones are

marked with *. The ones marked with are50RVK

unit-vi wireless and broadband network

Documents