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Broadband/Wireless for Peadar. Transmission Theory. What happens between the time that a signal begins to propagate down a wire and the time that it reaches its destination Digital Transmission Speed “How fast is your internet connection?” www.bandwidthplace.com/speedtest Bit Rate
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Transmission Theory • What happens between the time that a signal begins to propagate down a wire and the time that it reaches its destination • Digital Transmission Speed • “How fast is your internet connection?” • www.bandwidthplace.com/speedtest • Bit Rate • Bits per second • Number of information bits which can be transferred in a single second • Information bit being a 1 or 0
Transmission Theory • Messaging through closed medium • Unshielded Twisted Pair (UTP) • Copper wire • RJ-45 Jacks • Optical Fibre • Uses light rather voltage to send 1 & 0
Modems • Ordinary telephone lines • Very useful for low-speed data transmission • Most homes already have a phoneline, thus no need for IT investment • Analog transmission • Computers work with digital transmission • Modem transforms digital computer signals into an analog form and back into digital signals • Internal, External, PCI Card (Laptop)
Modem Standards • Speed Standards • V.90 allows modem to receive at 56kbps & send at 33.6 • V.34 -> 33.6kbps • V.32 -> 14.4kbps • Error Correction and Data Compression Standards • V.42 allows retransmitting information that was garbled during transmission
Modem Alternatives • Speed Problem • Analog phone line has a max of 33kbps for transmission • Higher Speed Connections needed which are called broadband access services • Alternatives to Modems • Broadband • ISDN, DSL, ADSL, Cable, Satellite etc.
Broadband Infrastructure • What is broadband? • High-speed internet access which allows clients to connect to the Internet up to 30 times faster than using a dial-up (DSL) • Any “always on, high speed connection” to the Internet • Increased business usage of Internet resources • File sharing • File downloading and uploading • Web Surfing • Broadband Information Web Site • www.broadband.gov.ie
Broadband Infrastructure • Broadband Technologies • ADSL • CABLE • Fixed Wireless Broadband • Satellite • Cost • PC, Modem, Monthly Connection Cost
How to define broadband? • Narrowband • Up to 2 ISDN at 128k in both directions • Midband • Up to 512K download and 256k upload • Broadband • Above 512k download and 256k upload
Broadband Infrastructure • Contention • Most broadband access services share a single connection path between many customers - this is referred to as contention. A contention ratio of 40:1 means that up to 40 customers are sharing the same connection. • Low usage -> contention does not pose a problem • High usage -> the quality of the connection can deteriorate if many customers use the connection at the same time. Most of the time, you should be able to connect to 75% - 90% of the top speed available at your location
ISDN • Integrated Services Digital Network (ISDN) • ISDN is a purely digital system • ISDN is a dial-up system (not always “on”) • Installation and usage dependend on Telecoms • ISDN modem needed • Multiplexing • Cost of running ISDN
DSL • Digital Subsriber Line (DSL) Modems • Entirely digital service offered by Telecoms • Faster than ISDN, offering transmission speeds of 384 kbps to several megabits per second • ADSL – Asymmetric DSL • High downstream speed, lower upstream speed • Suitable for www surfing @ home
Why Broadband? • FastUp to 40 times faster than traditional dial-up internet access. • Always-OnNo dial-up, no time restrictions, no cut-offs. • ConvenientAccess the internet and talk on the telephone at the same time. • EntertainmentExperience smooth digital video and CD quality music • ValueOne flat fee per month with no additional internet call charges
The Knowledge Society ??? While the industrial age was primarily driven by productivity increases due to greater power (Electric) Economic progress in the 21st century will be driven primarily by productivity increases due to greater knowledge – the ability to access quickly large amounts of information, to process it in concert with others and to use it to produce and consume more efficiently.
Terabits of IP traffic per year (with a % break-down of that traffic for the years 1999 and 2005) Tbps 21% 45% 24% 10% 3.5 3% 24% 20% 43% 3 2.5 Rich Media & Streaming Peer to Peer Server to Server Web Pages 2 1.5 1 0.5 0 1999 2000 2001 2002 2003 2004 2005 IP TRAFFIC GROWTH
DOWNLOAD DOWNLOAD CONNECTION CONNECTION over 14 days, 12 over 14 days, 12 Dial-up 14.4 kbps Dial-up 14.4 kbps over 3 days, 5 over 3 days, 5 Dial-up 56.6 kbps Dial-up 56.6 kbps hours hours Modem at 640 Modem at 640 kbps kbps over 6 hours over 6 hours T1 at 1.5 Mbps T1 at 1.5 Mbps minutes minutes 10 Mbps 10 Mbps connection connection 21 minutes 21 minutes connection connection 2 minutes 2 minutes Example of Capacity Requirement • 2-hour movie with mpeg-1 compression – File Size 2 GB. • Video-on-demand - download times must be shorter than the play time. TIME hours DSL/Cable 2 hours, 45 5 Mbps connection 43 minutes 100 Mbps
Broadband Stats • www.oecd.org (June 2005) • 137m broadband connections (OECD countries), up 18m compared to January 2005 • DSL:60% • Cable:32% • Other:8% (Fixed wireless, fibre, LAN)
Case Study: Singapore • Singapore was the first country in the world to deploy ADSL commercially when SingTel launched its Magix service in November 1997 • 2003 Summary Report • “Intelligent Nation 2015” • www.in2015.sg
Case Study: SEISS • Broadband Infrastructure Case Study: • SEISS • South East Information Society Strategy (Ireland)
SEISS ICT Strategy & Action PlanProgramme Elements Integrated Approach to Regional ICT Development
Phase 1 Municipal Fibre Optic Networks Phase 2 Regional Interconnectivity Regional Municipal Broadband Fibre Optic Network
Typical Municipal Fibre Optic Town/City Network Tele Hub Telco Provider POPs Fas Centre Institute of Technology Fas Centre Govmnt. Dept. Railway Station ESAT School Local Authority Health Board Industrial Park Bank Industrial Park Enterprise Centre Library Industry School School Industry ESBi Transformer Station Eircom Exchange Hospital Switched SDH Unit, Waterford Network Services & Management Ethernet Connectivity for SMEs
MAN Project • So, what’s the big deal in getting there???? • ….and where do we lay the cable? • Highways • Water • Gas
MAN - Traditional Utility Trenching • Conventional Open Cut Dig
MAN • Conventional Open Cut Dig
MAN - Cable Installation Co-Location Build
Internet by Satellite • Internet -> Location doesn’t matter • Not for infrastructure • Rural areas still have a “infrastructural” disadvantage • Use satelite broadband access to overcome this issue • 2004 (USA) • 3.9m homes will have high-speed service via satellite • 9.6m homes with cable modems • 7m homes with digital lines (DSL & ADSL)
Internet by Satellite • Worldwide, data over cable exceeds wireless delivery of broadband Internet access • Satellite Access Options • One way • Uplink is negotiated through traditional phone modem • Used mainly for downloading • Not good for web browsing or online gaming • Two way • 2 Mbps uplink & 38 Mbps downlink
Satellite Broadband Infrastructure • Costs? € 1 = 2.04 SGD (November 2005) • Ireland: Once off installation € 125 + €270/quarter • From €1205 to €6300 (2MB per second) • Satelite broadband access • SOHO Bandwidth costs € 49.99 per month for 500 MB download, € 0.10 per MB thereafter.USB Satellite Receiver Purchase € 290.00 • Enterprise Hardware Rental € 285.00 per month, Bandwidth costs € 500.00 per month for 1 GB upload/download, € 0.21 per MB thereafter
M-Commerce & Wireless Communications • Introduction • How is wireless technology used? • Wireless Applications • Advantages & Disadvantages
Introduction • Mobile users connected world-wide (Dataquest) • 1998: 200m • 2000: 400m • 2003: 900m • Mobile penetration in Europe (Dataquest) • 1999: 50% • 2000: 55% • 2003: 65% • Mobile connections outline fixed lines (2005) • Phone land lines -> 1.900.000 • Mobiles -> 3.800.000
Bluetooth • Bluethooth • Cable Nightmare • Solution? • Bluetooth • …open standard for short range voice and data communication • …short-range radio connection between devices • …wireless comunication with a difference • …name was chosen to hightlight potential of this technology to unify the telecommunications and computing industries
Bluetooth • Bluetooth Device • Communication via radio transceivers/radio modules • Link manager (software) identifies other Bluetooth devices, creates the link, and sends/receives data • 10 meter range, up to 1Mbps transmission rate • Transmission through physical barriers, like walls to one or many devices at the same time • 1500+ difference vendors have agreed to distribute Bluetooth enabled devices
Piconet Every Bluetooth device can simultaneously maintain up to 7 connections, but only one active connection at the time. These groups (maximum of 8 devices: 1 host and 7 slaves) are called Piconets
Bluetooth • 1994 • Ericsson, Nokia, IBM, Toshiba, Intel hit upon the idea of bluetooth • 1998 • Special Interest Group officially launched, couple of hundred members • 2000 • SIG has over 2000 signed up members • http://www.bluetooth.com
Wireless LANs • The Big Thing in local area networking today • Gives mobility to users within the corporate premises • Not a competitor for the main wired Ethernet LAN today; extends the wired LAN’s resources to mobile users
Wireless LAN (WLAN) Access Point Large Wired LAN Control Message Access Point Ethernet Switch UTP Radio Transmission Laptop Mobile Client Router Access point controls wireless stations (transmission power, etc.) Server Internet
Typical 802.11 Wireless LAN Operation with Access Points Ethernet Switch 802.3 Frame 802.11 Frame UTP Radio Transmission Access Point A Laptop 802.3 Frame Access point bridges the networks (translates between the 802.11 wireless frame and the Ethernet 802.3 frame used within the LAN) Client PC Server Large Wired LAN
Wireless Access Point and Wireless PC Card NIC. Access Point Wireless NIC
WLAN • 802.11b • 112 meter range • Up to 11Mbps • New Version 802.11a • 90 meter range • Up to 54Mbps • 802.11g • Added Security
802.11 Security • Automated Drive-By Hacking • Can read traffic from outside the corporate walls • Can also send malicious traffic into the network
802.11 Security • No Security by Default • In older products, the installation default was to have no security at all No Security No Security