REMOTE ACCESS Lecture II Datacom II REMOTE ACCESS

REMOTE ACCESS Lecture II Datacom II REMOTE ACCESS 1

REMOTE ACCESS What Is It ? Accessing a network from a remote location ä Accessing the LAN from a remote location ä Accessing the Internet Datacom II REMOTE ACCESS 2

REMOTE ACCESS WHY REMOTE ACCESS ? ä E-Mail and File Transfers ä Online transaction processing ä Emphasis on telecommuting ä Price reductions in portable systems ä Competitive Pressures Datacom II REMOTE ACCESS 3

REMOTE ACCESS TYPES OF REMOTE ACCESS Datacom II REMOTE ACCESS 4

REMOTE ACCESS USERS HOME OFFICE SOHO REMOTE ACCESS TRAVELLING EMPLOYEE OUTBOUND Datacom II REMOTE ACCESS 5

REMOTE ACCESS FUTURE ARCHITECTURE Data Management SERVER Application Logic Remote Middleware WAN SATELLITE WIRELESS ISDN ADSL MODEM CABLE MODEM Remote Middleware MOBILE/ REMOTE CLIENT Datacom II Data Management Application Logic Presentation REMOTE ACCESS Source: -Gartner Group 6

REMOTE ACCESS FEATURES OF THE ARCHITECTURE ä STORE AND FORWARD ä SINGLE SESSION COMMUNICATIONS ä NETWORK INDEPENDENCE Datacom II REMOTE ACCESS 7

REMOTE ACCESS BANDWIDTH DEMAND FORECAST TOTAL DESIRED BANDWIDTH : - 528 Kbps Source: -Gartner Group Datacom II REMOTE ACCESS 8

REMOTE ACCESS OPTIMIZATION TECHNIQUES ä GENERIC TECHNIQUES ä LAN BASED TRAFFIC OPTIMIZATION ä APPLICATION DRIVEN TECHNIQUES Datacom II REMOTE ACCESS 9

REMOTE ACCESS GROWTH IN NUMBER OF REMOTE ACCESS USERS No. of Users (in Millions) Source: Gartner Group Datacom II REMOTE ACCESS 10

REMOTE ACCESS SUMMARY TILL NOW… ä ä ä More than 32 m remote users by 2000. By 2001, Remote Access will be a necessity not a luxury. Bandwidth requirement will shoot up. By, 2001 new applications for Deferred Remote Access will be written. By 2001, Remote Performance Optimization standards will come in place. Datacom II REMOTE ACCESS 11

REMOTE ACCESS Datacom II REMOTE ACCESS 12

REMOTE ACCESS DIAL UP MODEMS TILL NOW…. Older Standards V. 32 bis V. 34+ Datacom II 33. 6 Kbps 28. 8 Kbps 14. 4 Kbps V. 34+ V. 34 V. 32 bis 9600 bps V. 32 300 bps REMOTE ACCESS 13

REMOTE ACCESS DIAL UP MODEMS WHAT NOW…. 56 Kbps ä ä Kflex 56. (Motorola) X 2(3 Com) Kflex 56 X 2 33. 4 Kbps V. 34 Datacom II REMOTE ACCESS 14

REMOTE ACCESS THE 56 K TECHNOLOGY Datacom II REMOTE ACCESS 15

REMOTE ACCESS FEATURES OF THE 56 K TECHNOLOGY ä SERVICES OVER REGULAR PHONE LINES. ä 100% DIGITAL NETWORK EXCEPT THE LOCAL LOOP. ä DOWNLOADS FROM INTERNET, CORPORATE NETWORKS AT 56 Kbps. ä BACKWARD COMPATIBLE. Datacom II REMOTE ACCESS 16

REMOTE ACCESS DIFFERENCE BETWEEN 56 K AND V. 34 TECHNOLOGY ä ä 100% DIGITAL CONNECTION EXCEPT THE LOCAL LOOP. ASYMMETRICAL CONNECTION. UPSTREAM SPEED LIMITED DUE TO A/D CONVERSION. ä USE “PAM” IN DOWNSTREAM AND “QAM” IN UPSTREAM. ä Datacom II ä ä OPTIMIZED FOR END TO END ANALOG CONNECTIONS. SYMMETRICAL CONNECTION. A/D CONVERSION TAKING PLACE AT BOTH ENDS HENCE LIMITING SPEED. USES “QAM” IN BOTH DIRECTIONS. REMOTE ACCESS 17

REMOTE ACCESS 56 K DIAL UP MODEM REQUIREMENTS ä DIGITAL AT ONE END. ä 56 K TECHNOLOGY SUPPORT AT BOTH ENDS. ä ONE ANALOG TO DIGITAL CONVERSION. Datacom II REMOTE ACCESS 18

REMOTE ACCESS THE 56 K MODEM TECHNOLOGY SUPPLIERS ä DEVELOPED BY ROCKWELL AND LUCENT. Datacom II ä DEVELOPED BY US ROBOTICS AND 3 COM. REMOTE ACCESS 19

REMOTE ACCESS DISADVANTAGES OF 56 K MODEMS ä USEFUL ONLY FOR INTERNET DOWNLOADS. ä NO STANDARDIZATION FROM ITU-IT. ä NO VIDEOCONFERENCING AND MULTIMEDIA APPLICATIONS POSSIBLE. Datacom II REMOTE ACCESS 20

REMOTE ACCESS Datacom II REMOTE ACCESS 21

REMOTE ACCESS WHAT IS CABLE MODEM TECHNOLOGY ? ä HIGH SPEED DATA TRANSFER VIA THE BROADBAND CABLE TV NETWORK. Datacom II REMOTE ACCESS 22

REMOTE ACCESS TYPICAL SCENARIO…. . COAXIAL CABLE TWISTED PAIR SERIAL CABLE Datacom II REMOTE ACCESS 23

REMOTE ACCESS WITH CABLE MODEM TECHNOLOGY…. COAXIAL CABLE TWISTED PAIR CABLE MODEM Datacom II REMOTE ACCESS 24

REMOTE ACCESS WHAT IS A CABLE MODEM ? ä ä ä ACTS AS A BRIDGE, SPANNING THE CABLE MEDIA’S ACCESS PROTOCOL AND THE PC’S COMMUNICATION PROTOCOL. OPERATES AT LAYER 1 AND LAYER 2. HAS CONNECTORS FOR POWER, VIDEO F AND ETHERNET CONNECTOR. Datacom II REMOTE ACCESS 25

REMOTE ACCESS CABLE TV PRIMER ä ä ä COAXIAL CABLES: -330 Mhz or 450 MHz. DOWNSTREAM VIDEO: -50 Mhz-750 Mhz. UPSTREAM VIDEO: -5 Mhz-42 Mhz. STANDARD TV CHANNEL OCCUPIES 6 Mhz. TRADITIONAL TV SYSTEM: -60 CHANNELS. Datacom II REMOTE ACCESS 26

REMOTE ACCESS BANDWIDTH ALLOCATION …. 750 Mhz 42 Mhz 5 Mhz Datacom II REMOTE ACCESS 27

REMOTE ACCESS CABLE MODEM SPEEDS Datacom II REMOTE ACCESS 28

REMOTE ACCESS CABLE MODEM SPEEDS Datacom II REMOTE ACCESS 29

REMOTE ACCESS SERVICES PROVIDED BY CABLE MODEMS ä INTERNET ACCESS ä ELECTRONIC MAIL ä REMOTE ACCESS TO CORPORATE LAN. Contd…. Datacom II REMOTE ACCESS 30

REMOTE ACCESS SERVICES…… ä INTEGRATED COMPUTER/TV ACCESS. ä BANK AT HOME SERVICES. ä HOME ENTERTAINMENT. Datacom II REMOTE ACCESS 31

REMOTE ACCESS Datacom II REMOTE ACCESS 32

REMOTE ACCESS CABLE MODEM NETWORK: -AN EXAMPLE Datacom II REMOTE ACCESS 33

REMOTE ACCESS EXPLANATION…. ä Super. Headend: -Heart of the System ä LCp: -Personal Cable Modem ä LCw: -Workgroup Cable Modem. ä LCb: -Multiuser Cable Modem. Datacom II REMOTE ACCESS 34

REMOTE ACCESS CABLE MODEMS: --AVERAGE COST Datacom II REMOTE ACCESS 35

REMOTE ACCESS BANDWIDTH COST COMPARISON $/Kbps Datacom II REMOTE ACCESS 36

REMOTE ACCESS Datacom II 1. Time Warner Cable 29, 000 2. Media. One 17, 000 14, 000 3. Cox Communications 16, 000 4. Rogers Cablesystems 14, 000 5. Comcast 5, 800 6. Videotron 5, 000 7. Shaw Communications 4, 500 8. COGECO 4, 000 9. Tele-Communications Inc. 2, 400 10. Adelphia 2, 000 11. Cablevision Systems 1, 400 12. Jones Intercable 4, 000 Other 4, 000 TOTAL 111, 100 REMOTE ACCESS 37

REMOTE ACCESS CABLE MODEM--SUBSCRIBER PROJECTIONS Datacom II REMOTE ACCESS 38

REMOTE ACCESS CABLE MODEMS: --UNIT SALES PROJECTIONS Datacom II REMOTE ACCESS 39

REMOTE ACCESS DISADVANTAGES OF CABLE MODEMS ä ä HUGE INVESTMENT BY MSO. RELIABLE MANAGEMENT SYSTEM REQUIRED. NO INTEROPERABILITY BETWEEN DIFFERENT MODEMS. UPSTREAM SPEEDS NOT STANDARDIZED. Datacom II REMOTE ACCESS 40

REMOTE ACCESS PRESENT SCENARIO ä NO STANDARDS. ä PRESENT CUSTOMERS ARE MSO’s. ä NO SUPPLIERS TO PROVIDE END TO END SOLUTIONS. Datacom II REMOTE ACCESS 41

REMOTE ACCESS CABLE MODEMS--FUTURE ä ä ä STANDARDIZATION FOR DOWNSTREAM AND UPSTREAM SPEEDS. INTEROPERABILITY BETWEEN DIFFERENT MODEMS. REDUCTION IN COSTS. CUSTOMERS WILL BE END USERS. SUPPLIERS WITH END TO END SOLUTIONS. Datacom II REMOTE ACCESS 42

REMOTE ACCESS Datacom II REMOTE ACCESS 43

REMOTE ACCESS WHAT IS ADSL ? ä ASYNCHRONOUS DIGITAL SUBSCRIBER LINE--A NEW MODEM TECHNOLOGY. Datacom II REMOTE ACCESS 44

REMOTE ACCESS ADSL FEATURES ä ä ä HIGH SPEED NETWORK ACCESSIBILITY. HIGH SPEED REMOTE ACCESS. VIDEO ON DEMAND. CONSTANT CONNECTIVITY. NO NEED TO ADD NEW PHONE LINES. Datacom II REMOTE ACCESS 45

REMOTE ACCESS ADSL : - THE NETWORK Datacom II REMOTE ACCESS 46

REMOTE ACCESS ADSL…. SPEEDS Datacom II ä ADSL MODEMS CONSISTENT WITH EUROPEAN AND NORTH AMERICAN DIGITAL HIERARCHIES. ä VARIABLE DATA RATES. REMOTE ACCESS 47

REMOTE ACCESS TECHNOLOGY DESCRIPTION…Requirements ä FULL USE OF COPPER LINE FREQUENCY SPECTRUM(1. 1 Mhz). ä ADVANCED CODING/DECODING METHOD. ä ABILITY TO WORK WITH POTS ON SAME COPPER LINE. ä AN EFFICIENT ERROR CORRECTION CODE. Datacom II REMOTE ACCESS 48

REMOTE ACCESS TECHNOLOGIES USED BY ADSL ä CODING: --DMT OR CAP ä CODE AND ERROR CORRECTION ä FRAMING AND SCRAMBLING Datacom II REMOTE ACCESS 49

REMOTE ACCESS ADSL: --BANDWIDTH ALLOCATION Datacom II REMOTE ACCESS 50

REMOTE ACCESS ADSL: --CODING SCHEMES Datacom II REMOTE ACCESS 51

REMOTE ACCESS ADSL: --DMT CODING TECHNIQUE Datacom II REMOTE ACCESS 52

REMOTE ACCESS ADVANTAGES OF DMT ä BETTER PERFORMANCE ä BIT RATE FLEXIBILITY ä RESISTANCE TO IMPULSE NOISE ä ATM SUPPORT Datacom II REMOTE ACCESS 53

REMOTE ACCESS ADSL: --DISTANCE LIMITATIONS Datacom II REMOTE ACCESS 54

REMOTE ACCESS ADSL PRODUCTS FROM COMPANIES Datacom II REMOTE ACCESS 55

REMOTE ACCESS ADSL : -- WHAT IS NEEDED ? Datacom II REMOTE ACCESS 56

REMOTE ACCESS ADSL PROVIDER IN HOUSTON ä SOUTH WESTERN BELL TEST SITE: -SHELL Datacom II REMOTE ACCESS 57

REMOTE ACCESS DIFFERENT x. DSL Datacom II REMOTE ACCESS 58

REMOTE ACCESS ADSL : -ISSUES TO BE RESOLVED ä HIGH SPEED x. DSL, WHICH ONE? ä LAYER 1 CAP vs DMT ä LAYER 2 ATM vs ETHERNET ä LAYER 3 PPP OR NOT? Datacom II REMOTE ACCESS 59

REMOTE ACCESS GLOBAL SYSTEM FOR MOBILE Datacom II REMOTE ACCESS 60

REMOTE ACCESS OVERVIEW OF THE CELLULAR SYSTEM Datacom II REMOTE ACCESS 61

REMOTE ACCESS OVERVIEW OF CELLULAR CONCEPT ä HEXAGON GEOMETRY ä EACH CELL HAS TRANSMITTER ä FREQUENCY REUSE ä HANDOFF Datacom II REMOTE ACCESS 62

REMOTE ACCESS WHAT IS GSM ? ä A Second Generation Cellular System. ä First Digital Cellular System. ä Supports mobile communications in the 900 Mhz and 1. 8 Ghz range. Datacom II REMOTE ACCESS 63

REMOTE ACCESS GSM: -SERVICES AVAILABLE NOW ä TELESERVICES. ä DATA SERVICES: Packet Switched Data at 300 bps-9. 6 Kbps. ä ISDN SERVICES. Datacom II REMOTE ACCESS 64

REMOTE ACCESS GSM FUTURE Datacom II REMOTE ACCESS 65

REMOTE ACCESS GSM-HSCSD ä High Speed Circuit Switched Data. ä Will boost user Capacity to 64 Kbps. ä Designed for existing Infrastructure. Datacom II REMOTE ACCESS 66

REMOTE ACCESS GSM-GPRS ä General Packet Radio Service ä Suitable for Bursty nature data transmission. ä Ideal for e-mail and Database access. ä Cost effective. ä Connectivity at 64 Kbps. Datacom II REMOTE ACCESS 67

REMOTE ACCESS Datacom II REMOTE ACCESS 68

REMOTE ACCESS SATELLITE BASICS Datacom II REMOTE ACCESS 69

REMOTE ACCESS SATELLITE COMMUNICATION BANDS Datacom II REMOTE ACCESS 70

REMOTE ACCESS Ka BAND SATELLITE PROJECTS Datacom II REMOTE ACCESS 71

REMOTE ACCESS IRIDIUM LEO SATELLITE SYSTEM ä ä ä Motorola’s Global Mobile Satellite Project. Communication System for Voice, Data Fax and Paging. 66 LEO Satellites. Multiple Access Scheme: -FDMA/TDMA. Frequency Band: -Ka Band(19. 4 -19. 6 Ghz for Downloads) Ka Band(29. 1 -29. 3 Ghz for uplinks) L-Band(161 Mhz) Year of Operation: -1998 Datacom II REMOTE ACCESS 72

REMOTE ACCESS IRIDIUM SATELLITE SYSTEM Datacom II REMOTE ACCESS 73

REMOTE ACCESS THE TELEDESIC NETWORK Datacom II REMOTE ACCESS 74

REMOTE ACCESS TELEDESIC NETWORK-FEATURES ä Broadband Network of LEO Satellites. ä 288 LEO Satellites. ä Frequency Band: --Ka ä Uplink Frequency: -18. 8 Ghz-19. 3 Ghz ä Down. Link Frequency: -28. 6 Ghz-29. 1 Ghz Contd…. . Datacom II REMOTE ACCESS 75

REMOTE ACCESS TELEDESIC…. . . ä SPEEDS: -UPLINK-2 Mbps Downlink-640 Kbps ä Uses fast Packet Switching. ä Bandwidth on demand. ä Multiple access technique: -TDMA ä High Mask Angle: -40 Datacom II REMOTE ACCESS 76

REMOTE ACCESS THE HUGHES GEO NETWORK ä Broadband Satellite Network using GEO. ä 8 GEO Satellites. ä Frequency Band: -Ka(17. 7 Ghz-30 Ghz). ä Uplink Speeds: -6 Mbps. ä Intersatellite Links ä Interoperability with terrestrial networks. Datacom II REMOTE ACCESS 77

REMOTE ACCESS THE HUGHES NETWORK…… ä Bandwidth On Demand. ä Uses Spot Beam Technology. ä Service Begins in 2001. Datacom II REMOTE ACCESS 78

REMOTE ACCESS THE SPOT BEAM TECHNOLOGY Datacom II REMOTE ACCESS 79

REMOTE ACCESS BANDWIDTH ON DEMAND Datacom II REMOTE ACCESS 80

REMOTE ACCESS VSAT ä Stands For Very Small Aperture Terminal. ä Satellite driven Service. ä Network consists of Hubs, Outdoor Units. Datacom II REMOTE ACCESS 81

REMOTE ACCESS VSAT NETWORK Datacom II REMOTE ACCESS 82

REMOTE ACCESS VSAT-CONFIGURATION Datacom II REMOTE ACCESS 83

REMOTE ACCESS-FUTURE U. S Consumer Internet Access in 2002 --Main Access Method Source: -Gartner Group Datacom II REMOTE ACCESS 84

REMOTE ACCESS-FUTURE U. S Enterprise Remote Access in 2002 -Main Access Method Source: -Gartner Group Datacom II REMOTE ACCESS 85

REMOTE ACCESS Datacom II REMOTE ACCESS 86

REMOTE ACCESS BASICS : -GEOSTATIONARY SATELLITE Datacom II REMOTE ACCESS 87

REMOTE ACCESS SATELLITE COMMUNICATION BANDS Datacom II REMOTE ACCESS 88