What is network?
Types of network
◦ LAN – Local Area - Ethernet◦ WAN – Wide Area - Internet◦ MAN – Metro. Area - LAN<=50km◦ Wireless - WiFi◦ PAN – Personal Area – Bluetooth◦ Mobile Networks - CDMA/GSM/3G/4G etc◦ WSN - Sensor Networks◦ RFID (Radio Frequency Identification)
Image Source: http://oscar.iitb.ac.in/images/weeklyimages/Networking/Bluetooth.jpg
Overview A typical Network
Repeater◦ Signal boost◦ Example: Hub
Bridge◦ Connections same types of
networks◦ Example: Switch
Routers◦ Connects different types of
networks Gateway
Connects different types of protocols
Picture Source: http://img.zdnet.com/techDirectory/WIFIBRDG.GIF
Explanation Example
Server Port Numbers 80 – HTTP 20/21 – FTP 25 – SMTP 53 – DNS Client Port Numbers 1025 - 65535
Image Source: http://www.isaserver.org/img/upl/2004rp21109170267623.gif
Type of Cables for LAN RJ 45 Cable
RJ = Registered Jack RJ 11 – Telephone RJ 45 – Ethernet
◦ Straight Through◦ Crossover◦ Rollover
Picture Source: http://en.wikipedia.org/wiki/Ethernet
http://www.bizwaremagic.com/quick_internet_history.htm
http://www.walthowe.com/navnet/history.html
CyberAtlas.com
History ARPANET (Advanced Research Projects Agency Network) was the first packet switching network
created by United States Department of Defense during cold war.
Internet was first brought online in 1969 connecting 4 computers between UCLA, Stanford Research Institute, UCSB, and the University of Utah
Tim Berners-Lee joined with others, proposed a new protocol in 1989 for information distribution which is now known as World Wide Web.
It took 38 years for radio to reach 50 million users, 13 years for TV, and only 5 years for the Internet.
http://www.internetworldstats.com/stats.htm
Image Source: http://www.teach-ict.com/technology_explained/packet_switching/packet.switching.gif
http://visualroute.visualware.com/
cmd – tracert www.websitename.com
Link What is inside the net?
http://video.google.ca/videoplay?docid=4523214973725842000&ei=JTW6Su_3PI-MqAKnouzyAQ&q=warriors+on+the+net&hl=en#
http://www.youtube.com/watch?v=Ve7_4ot-Dzs
Picture Source: http://www.portices.fr/formation/Res/Internet/Res/InternetMonde.gif
Overview Complications
Image Source: http://filipspagnoli.files.wordpress.com/2009/02/china-censorship-of-the-internet-cartoon.gif
http://sohomediatech.com/images/SOHO-MediaTech-wired-network.jpg
http://www.securitystats.com/
At its peak infection rate, about 1 in 12 emails on the Internet were MyDoom Viruses
It is estimated that PC Viruses cost businesses approximately $55 Billion in damages in 2003.
FTC received 161,000 identity theft complaints last year, the FBI estimates the actual number of victims is probably closer to 500,000
Virus – Inside the machine Worm – Machine to machine Spyware – Collect information from the computer Adware – Ads popup Trojan – Type of malware control by a hacker Phishing – fool the recipient by asking personal
information Network intrusions Many more
Biometric
Firewall
Cryptography
Anti-Spyware
Antivirus
IDS
Mgmt rules
Security