The Influence of the Internet

Transcription

1 The Influence of the Internet Eran Treister Liron Pergament General Background Internet Protocols Web Browsers Search Engines Agenda Modems Web Hosting Threats Security Internet Opportunities 2 General Background 1876 Alexander Graham Bell invents the telephone. General Background 1969 ARPA-Net, the forerunner of the Internet, is established Bell Labs develops the first modem. 3 4 General Background 1981 Minitel (Teletel) is deployed across France by French Telecom. General Background DCA and DARPA establish the TCP/IP protocol for ARPANET 1990s The term Internet appears

2 Internet Protocols The Internet is based on the 4-layer model. Created in the 1970s by DARPA. The structure of Internet protocols is still closely reflected by the TCP/IP model. Internet Protocols This 4-layer model has: Layer 4: Application layer. Layer 3: Transport layer. Layer 2: Network layer. Layer 1: Physical layer 7 8 World Wide Web 1989 Tim Berners-Lee proposes the basic concept of the Web Creates HTML, HTTP, URL: Writes the prototype for the World Wide Web. In late 1971, Tomlinson developed the first ARPANET application. Until the 1980s FTP provided services for ARPANET. Historical addresses till 1982: utzoo!decvax!harpo!eagle!mhtsa! ihnss!ihuxp!grg s Early 1980's: the SMTP protocol was developed Creation of BITNET 1997 Hotmail released first free webmail. Web Browsers The first web browser- WorldWideWeb. Written in 1990 by Tim Berners-Lee. Displayed HTML pages Downloaded and opened most file types

3 Mosaic was the first popular World Wide Web browser. Developed by Eric Bina and Marc Andreessen in Released in Web Browsers Images were embedded in the text. Added graphics to previous text-based software Mosaic Browser Netscape Navigator In 1994, Mosaic was renamed to Netscape Navigator. Text and graphics appeared on the screen as the web page downloaded Internet Explorer In 1995, Microsoft licensed Mosaic from Spyglass as the basis of Internet Explorer The Browser Wars The first browser war: Internet Explorer vs. Netscape Navigator The Browser Wars The second browser war: Internet Explorer vs. Mozilla Firefox Vs. Vs. By the end of 2006, the usage share of Netscape browsers had fallen from over 85% in the mid 1990s, to less than 1% : Peak of 95%. Since Firefox's release, its market share has grown to 15.1%

4 The very first tool used for searching on the Internet was Archie Search Engines Search Engines In 1991 the Gopher protocol was created. Allowed storing and searching large repositories of information. Implemented in Could not search by file contents, only by file name. Select Fun & Games Search Engines Veronica - Very Easy Rodent-Oriented Net-wide Index. Jughead - Jonzy's Universal Gopher Hierarchy Excavation And Display. Searched files in Gopher index systems. Search Engines The first "full text" crawler-based search engine was WebCrawler, which came out in Deactivated in In 1998, Larry Page and Sergey Brin created a new kind of server environment that used low-end PCs. Around 2001, Google rose to prominence. Google uses an algorithm called PageRank. Google is currently the most popular search engine

5 How Search Engines Work How Search Engines Work Web Crawling Indexing Searching A crawler reads and stores information regarding web site pages. Data is indexed and stored in data structures. Searching the engine provides a listing of bestmatching web pages Modem Development A device that converts between digital and analog signals. The first modems were developed in the 1950s. Modem Development The first commercial (dial-up) modem entered the communication market only in Invented by AT&T. Enabled full-duplex transmission Reached data rates of 300bps Modem Development In 1980 data rates reached 14.4 Kbps. Doubled in In 1996: 56 Kbps Modem Development In the late 1990s: broadband modems: Cable and ADSL. Enable connection speed of 2Mbit/s up to 50 Mbit/s

6 Wireless Modem Wireless data modems are used in the WiFi and WiMax standards. Give laptops and PCs access points to a network. Web Servers and Hosting Web servers are computers that host web pages. Web hosts are companies that provide space on servers. Can also provide data center space called colocation Web Hosting types Free for personal users. Shared shared by many users. Reseller clients become web hosts. Application specific blog, image, video, wiki farms. Clustered websites are not limited to one server. Google Servers Example Provides: High bandwidth Load balancing Fault tolerance Zip Created by Abraham Lempel and Jacob Ziv. Basis for Winzip. Improved the ability to transmit large amounts of data. Web Programming Tools Microsoft FrontPage, Adobe DreamWeaver ASP.Net XHTML JavaScript All WWW programming standards are defined by W3C

7 Flash Technology Internet Threats Introduced in Adds animation and interactivity to web pages. swf extensions. Trojan- Horse Virus Worm The First Viruses Elk Cloner (1982) by Richard Skrenta. The Jerusalem Virus A DOS file virus first detected in Jerusalem, Israel, in October Anti-Viruses since European Bernt Fix. Today McAfee VirusScan and Norton AntiVirus Threats over the Network - Examples IP Spoofing Stealth of Data Denial of Service

8 Firewalls Firewall s activity IP Level Access Control Placed between networks of different security level or trust. Creating VPN Application level filtering Authentication IP Level Access Control Packet Filtering Creating VPN Scanning of every packet according to a rules table. New York HEAD QUARTERS London Branch office Firewall Firewall Internet User User 45 Internet Opportunities 46 Software Customer Services Software customer services Instant messaging VoIP, Video. File sharing applications Mobility Commercial Growth Web 2.0 Automatic Software Updates. Long term service & maintenance

9 Instant Messaging Typed text communication over the Internet. Voice/Video Over IP VoIP is routing of voice conversations over an IP-based network. Once upon a time... Today File Sharing Applications Napster Today emule, Kaazaetc. Accessible in: Cellular phones PDAs, Palms ipaqs Internet in mobile Commercial Growth Commercialism through the net. Automatic customer service. Second generation of web-based communities and services which facilitate collaboration and sharing between users. People can upload as well as download. Examples: Wikipedia Facebook Web

10 Second Life 3-D Virtual world built by it s residents. References e-e.html age= ion/0,,sid26_gci211854,00.html References _papers/wilson/wilson_html/node4.html ms/history.htm ieeecs/ieeecs/about/history/timeline.pdf References tm /bltelephone.htm Backups.. Thank You!

11 Application Level Filtering Statefull Firewall Security Technologies - Firewalls Intranet Web Server External Web Server Statefull inspection - Application level filtering. Dynamic changes in the rule table. User Firewall Internal Network Internet 61 FTP Application Example 62 FTP Application Example User initiates a control channel User initiates a control channel Internal Network Firewall initiates a control channel Firewall Internet Static rule table blocks By adding dynamic communication the transmission is allowed from the outside Server initiates a transmission channel 63 Internal Network Internet Server initiates a transmission channel 64 Firewall Usage - NAT Public IPs Firewall : :X : :Y : :Y : :X 65 11