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Internet Policy Day 1 - Workshop Session No. 1 History and technical background Prepared for CTO by Link Centre, Witwatersrand University, South Africa Sessions Summary Day 1 – – Governance processes Interconnection and exchanges Session 5 Session 6 The impact of telecommunications regulation Internet specific policy issues Day 4 – – Session 3 Session 4 Day 3 – – History and technical background Market structure Day 2 – – Session 1 Session 2 Session 7 Session 8 Content on the Internet E-commerce issues Day 5 – – Session 9 Session 10 Internet tools for regulators Conclusion, review and evaluation CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 History and technical background The purpose of this session is to understand the basic design and functioning of the networks which make up the Internet. CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Topics of discussion How did the Internet develop? What kind of network is the Internet? Packet-based networks Backbone infrastructure Basic Internet protocol (TCP/IP) IP addresses How does data get from A to B? Infrastructure: Routers, Switches and Servers Higher level protocols Domain names CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How did the Internet develop? ARPANET (military) [1969 – 1980’s]: Research sponsored by the US Dept. of Defense, specifically, the Advanced Research Projects Agency (ARPA) Objective was to link geographically distant computers to allow remote access and sharing of data Network had to have no single point of failure CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How did the Internet develop? ARPANET (military) [1969 – 1980’s]: The Internet’s Grandfather, ARPANET, was born in late 1969 From the beginning ARPANET was packet-based, which has important ramifications on its operation (no single point of failure) Initially used NCP (Network Control Protocol), but adopted TCP/IP from 1973 onwards. CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How did the Internet develop? NSFNet (academia) [1980’s – 1991] By the mid-80’s ARPANET had grown into a widespread educational and scientific network Started to expand to other countries The backbone of this network (NSFNet) was funded by the National Science Foundation (NSF) CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How did the Internet develop? NSFNet (academia) [1980’s – 1991] Because it was government-funded, there remained restrictions on the commercial use of this backbone until 1991 CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How did the Internet develop? CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How did the Internet develop? ISPs and Telcos (business) [1991-2001] In the late eighties and early nineties, the backbone was commercialised and the Internet has grown exponentially since then CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 What kind of network is the Internet? The word “internet” network = interconnected computers internet = inter connected networks (archaic :-) Internet = The Internet CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 What kind of network is the Internet? Types of networks Circuit-based networks – Telephone networks – Power grids Packet-based networks – Post Office – The Internet CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Packet-based networks Unlike circuit-based networks, packet networks have no dedicated end-to-end connection A characteristic of these networks is the unpredictable nature of routing The Post Office runs a packet-based network The Internet is packet-based CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Backbone Infrastructure Copper cable Fibre-optic cable Wireless Satellite (VSAT) “Broadband” CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Basic Internet protocols (TCP/IP) TCP/IP = Transmission Control Protocol / Internet Protocol CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 IP addresses Numbers – IP addresses – IP numbers currently consist of four 8-bit numbers (e.g. 209.212.117.130) – We are running out of these numbers, hence the introduction of IP version 6 – IP -- what version are you using? (version 4) – NAT = Network Address Translation CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 How does data get from A to B? The transmission process is roughly as follows: – Data is split up into IP packets (TCP’s job) – Variable packet size – The destination of the packets are clearly labeled (IP address) – The packets are dumped into the closest part of the network to fend for themselves CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Internet infrastructure: Routers, Switches and Servers Bigger blocks Routers – routers direct TCP/IP packets to their destinations Switches – Tend to be simpler and faster than routers Servers – servers answer requests for information and serve information to others Speed – A connection is only as fast as its slowest link! CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Higher level protocols Other protocols TCP/IP is the basis for moving packets of data on the Internet, but that is all it does On top of this, different protocols are run to provide useful services or functions – – – – HTTP = Hyper Text Transfer Protocol (web) SMTP = Simple Mail Transfer Protocol (e-mail) POP3 = Post Office Protocol BGP = Border Gateway Protocol CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Domain names Names versus numbers – Recap: IP addresses (e.g. 109.212.117.130) – Humans are not good at remembering numbers, so domain names were created Generic versus geographic – – – – Generic: .com, .net, .org Special: .gov, .mil, .edu Little known domains: .int Country code: .uk, .za, .jp further split up, e.g. .co.za, .org.za, .gov.za. CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Domain names New domains – Generic: .biz and .info – Special: .museum and .aero “New” domains – .tv, .nu, .to, etc. CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Summary The Internet has had military, academic and commercial influences Different media (copper, fibre, wireless) are used for the Internet backbone The Internet uses TCP/IP packets IP addresses and domain names are used as identifiers Routers and switches move packets CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002 Quiz What does NCP stand for? What was the National Science Foundation’s backbone network called? What year were commercial restrictions on the Internet backbone dropped? What does BGP stand for? What version of IP are we using now? How many countries are not connected to the Internet? CTO / DFID Internet Policy workshop, Jamaica, 22-26 April 2002