The Internet
• The Internet is a global system of interconnected computer networks. It is a network of networks that consists of millions of private, public, academic, business, and government networks.*
*Wikipedia
History of the Internet
• Began with Point-to-Point (P2P) communication between computers (later Peer-to-peer)
• First version of the Internet was called APARNET– Mainly used by universities,
scientists, and government agencies to share information
• Internet2
Peer-to-Peer
• P2P – a network where one computer acts as a server or client for other computers
• Allows sharing access to various resources such as files
Centralized (Not P2P)
The Internet
• http://www.cablemap.info/• http://maps.level3.com/default/#.UUY45xw3t
2A• http://www.tatacommunications.com/downlo
ads/map/GFP-master_interactive_pdf-10-04-12.pdf
Internet Communications
• Sold by ISPs (Internet Service Providers)– Verizon, Comcast, Cox Cable, etc.
• LAN – Local Area Network• Dial-Up• Broadband• Wi-Fi• Satellite Broadband• Mobile Broadband
Routers and Modems
• Router – forwards data packets over computer networks to multiple computers
• Modem – (modulator-demodulator) encodes and decodes transmitted information. Connects to your ISP.
The Internet
• Every computer or device connected to the Internet has an IP address
• Instructions on where to send data and where to receive data
• http://www.whatismyip.com/
VoIP, IM, Video Chat
• Voice over IP• Alternative to traditional telephone• Ventrilo, Teamspeak, Raidcall
• Skype, Google Hangouts, Facetime
Internet - Domain Names
• Defines a realm of administrative autonomy, authority, or control
• US Department of Justice began using a tactic of seizing domain names, based on the legal theory that domain names are part of the property used by defendants to allegedly engage in criminal activities, and thus subject to forfeiture
The World Wide Web
• Not exactly the same as the Internet– Internet is a system of interconnected computer
networks– World Wide Web is a collection of text documents
and other resources linked by hyperlinks and URLs( Uniform Resource Locator)
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World Wide Web
Web BrowserSoftware that requests and
interprets web pages
Hypertext Transfer ProtocolProtocol for Web Browser and Web Server Communications
Web ServerComputer that holds Web
Pages and handles Browser requests
Web PagesElectronic Documents
Internet
Internet Backbone
• http://maps.level3.com/default/#.UUi-pRw3t2B
• http://www.verizonenterprise.com/ca/about/network/
Computer Communications
• Information broken into packets
• To avoid monopolizing a network• To recover in an event of an interruption
Computer Communications
• Bandwidth – the available or consumed data communication resources expressed in bits per second
• Latency – Time delay between communications
• Speedtest
Torrents
• Torrent file – a computer file that contains metadata about files and folders to be distributed, and usually also a list of the network locations of trackers
• Uses Peer-to-peer connections (P2P)
Magnet Links
• Trackers/hash code for the files are within the link
• Don’t need to download Torrent file anymore
Proxy Servers and VPN
• User connects to a proxy server as an intermediary to another server– i.e. Connect to a proxy server from another
country
• VPN – virtual private network: allows computer to send and receive across shared or public networks as if it were directly connected to the private network