internet basics 2k a presentation by patrick douglas crispen netsquirrel.com
TRANSCRIPT
Internet Basics 2KInternet Basics 2K
A presentation by
Patrick Douglas CrispenNetSquirrel.com
For More InformationFor More Information
http://netsquirrel.com/
Information about the Squirrel HuntInformation about TOURBUSA copy of this presentation
What IS the Internet?What IS the Internet?
“A network of networks based on the TCP/IP protocols, a community of people who use and develop these protocols, and a collection of resources that can be reached from those networks.”
-- Krol & Hoffman
Frequently Asked Frequently Asked QuestionsQuestions
• What IS the Internet (and what IS the World Wide Web)?
• How do the Internet and the Web work?
• What can I do on the Internet?• How do Internet addresses work?
Our GoalsOur Goals
• To answer some of the Net’s biggest Frequently Asked Questions (FAQs)
• To show you how the Internet really works
• To teach you how to read Internet addresses
• To do all of this in ENGLISH!!
GermanyGermany
• Self-sufficient cities
• The military needs 2 things to survive:– Supplies– Intelligence
WW2 GermanyWW2 Germany• Autobahn• Secure supply
lines• What happens to
German supply if a city is “lost?”
• Where is the Autobahn’s Headquarters?
I LIKE IKE!I LIKE IKE!
EISENHOWERINTERSTATESYSTEM
EISENHOWERINTERSTATESYSTEM
TEXAS’ Interstate TEXAS’ Interstate SystemSystem
• Safe supply lines
• Unlimited alternate routes
• Personal use
US Military US Military IntelligenceIntelligence
• Needed a way to hook up all of the mainframes in the USA
• Needed a system that could withstand a direct nuclear attack (well, not really)
• Needed a system without a central command
TEXAS and the TEXAS and the Internet?Internet?
• Cities = LANs or ISPs
• Interstates = Communications lines
• States = Regional Networks
IP PacketsIP Packets
• Everything that is sent over the Internet is sent in an IP Packet.
• IP Packets can contain anything
IP Packet RoutingIP Packet Routing
• TCP (Transmission Control Protocol)– Universal “rules”
of the Road
• IP (Internet Protocol) Addresses– 255.255.255.255
Domain Name System Domain Name System (DNS)(DNS)
Converts “English” nameswww.whitehouse.gov
into “Machine” (IP) names198.137.241.30
IP Packet RoutingIP Packet Routing
• Using your browser, you type in a URLhttp://www.whitehouse.gov/
• You “access” or “request” a Web page
IP Packet RoutingIP Packet Routing
• Your ISP “resolves” address– www.whitehouse.g
ov– 198.137.241.30
• Your ISP then puts your request into an IP packet (or a bunch of packets)
IP Packet RoutingIP Packet Routing
• The IP address is spray painted on the front windshield of the IP packet
• Your ISP ships the packet(s) to their router
• The router ships the packet(s) to the next “city”
Questions Routers Questions Routers “Ask”“Ask”
• Is this packet broken?
• Is this packet for me?
• In which general direction should this packet be sent?
At the White HouseAt the White House
• Mr. Bill’s Web Server receives your request
• It sends you the Web page you requested (including all of the text and multimedia)
• All of this is broken into a bunch of IP packets
IP Packet RoutingIP Packet Routing
• Mr. Bill’s ISP ships the packet(s) to his router
• The router ships the packet(s) to the next “city”
• THE CONNECTION IS DROPPED!
IP Packet RoutingIP Packet Routing
• The packets bounce through cyberspace
• Finally, the packets get to you, are put back in order, and the Web page appears
TEXAS and the TEXAS and the Internet?Internet?
• Each and every “intersection” (or “city”) is a router.
Pop QuizPop Quiz
• Is communication on the Internet (electronic mail, file transfers, etc.) instantaneous?
• Is the Internet now, or has it EVER been, free?
Two More QuestionsTwo More Questions
• Who owns the Internet?
• Who runs the Internet?– System of
networks (“backbone”)
What can I do on the What can I do on the Internet?Internet?
• Communicate• Login• Download• Publish• PLAY!
The Internet v. The The Internet v. The WebWeb
• What is the difference between the Internet and the World Wide Web?
• The Internet is ALL of the computers and ALL of the information available
• The World Wide Web is a subset of the Internet that contains hypermedia and is accessible through a Web browser.
How can I get on the How can I get on the Internet?Internet?
• Bulletin Board Service (BBS)• Commercial Online Service
– AOL / CompuServe– MSN
• Internet Service Provider (ISP)• Work/School
ModemsModems
• Converts digital signals to analog signals
• Modem at the other end turns the analog signal back into a digital signal.
Modem SpeedsModem SpeedsThe InternetBaud Speed Transfer Rate14.4 14,400 bps 1.76 Kb per second28.8 28,800 bps 3.56 Kb per second56 K 56,600 bps (*) 6.47 Kb per secondT1 1.5 million bps 183 Kb per secondT3 45 million bps 5.36 Mb per second
Modem SpeedsModem SpeedsThe InternetBaud Speed Transfer Rate14.4 14,400 bps 1.76 Kb per second
Internet2 (I2)Baud Speed Transfer RateOC-3 155 Mbps 18.54 Mb per secondOC-12 622 Mbps 74.16 Mb per secondOC-48 2.48 Gbps 295.64 Mb per second
:)
Internet AddressesInternet Addresses
• Machine addresses (IP or DNS)
• “Personal” addresses (e-mail)
• Resource addresses (Web pages, gopher directories, etc.).
Hi
Machine AddressesMachine Addresses
• IP Addresses– 255.255.255.255
• DNS Addresses– whitehouse.gov– www.yahoo.com– ua1vm.ua.edu
E-Mail AddressesE-Mail Addresses
• The world of e-mail is bigger than the Internet
• E-mail goes to a person, not just a machine
Parts of an E-mail Parts of an E-mail AddressAddress
• USERID– Name– Number– Combination of
both
Parts of an E-mail Parts of an E-mail AddressAddress
• The “at” sign– Above the number
2 on your keyboard
Parts of an E-mail Parts of an E-mail AddressAddress
• The address of the user’s mail server– IP Address 207.158.244.32
– DNS Address netsquirrel.com
Resource AddressesResource Addresses
Uniform Resource Locators (URLs)protocol://machine.address/dir/file
The /dir/file/ stuff may be optionalThe protocol, the ://, and the machine
address are REQUIRED
Resource AddressesResource Addresses
Uniform Resource Locators (URLs)protocol://machine.address/dir/file
http Web pagesftp File Transfer Protocolgopher Gopher Directories
Resource AddressesResource Addresses
Uniform Resource Locators (URLs)protocol://machine.address/dir/file
http://www.yahoo.com/
ftp://risc.ua.edu/pub/roadmap/
gopher://boombox.micro.umn.edu/
Resource AddressesResource Addresses
Uniform Resource Locators (URLs)protocol://machine.address/dir/file
REMEMBERREMEMBERE-mail addresses have @ symbols
URLs have ://
Resource AddressesResource Addresses
Uniform Resource Locators (URLs)protocol://machine.address/dir/file
The machine address can be either a DNS Address or an IP Address
Resource AddressesResource Addresses
Uniform Resource Locators (URLs)protocol://machine.address/dir/file
http://www.yahoo.com/
ftp://risc.ua.edu/pub/roadmap/
gopher://boombox.micro.umn.edu/
Internet AddressesInternet Addresses
• Machine Addresses– DNS or IP address
• Personal Addresses– [email protected]
• Resource Addresses– protocol://machine.address/dir/file
Internet AddressesInternet Addresses
• Machine Addresses– whitehouse.gov– 198.137.241.30
• Personal Addresses– [email protected]
• Resource Addresses– http://www.whitehouse.gov/
Machine Addresses -- Machine Addresses -- DomainsDomains
EDU EducationMIL MilitaryGOV Non-Military
Government Sites
COM Commercial
Organizations
[email protected]://www.yahoo.com/
Machine Addresses - Machine Addresses - DomainsDomains
NET Network Sites
ORG Other
OrganizationsUK United
KingdomCA CanadaAU Australia
[email protected]://www.yahoo.com/
Reading Internet Reading Internet AddressesAddresses
pbs.org
http://housing.msstate.edu/
141.211.83.37
Reading Internet Reading Internet AddressesAddresses
www.mcgill.ca
gopher://boombox.micro.umn.edu/
ftp://risc.ua.edu/pub/roadmap/
Reading Internet Reading Internet AddressesAddresses
204.162.80.181
http://204.162.80.181/
http://cnet.com/
Finding an E-mail Finding an E-mail addressaddress
• Search engines– WHOIS– Four-11
• The best way to find someone’s e-mail address is to call them on the telephone and ask them for it.
Crispen’s Five Crispen’s Five Antivirus RulesAntivirus Rules
• Buy a commercial antivirus program• Update your definitions weekly• Never double-click on a file, especially
an email attachment, without first virus checking it
• Turn on Macro Virus Protection in Word
• If you don’t know what an email attachment is, delete it.
Our GoalsOur Goals
• To answer some of the Net’s biggest Frequently Asked Questions (FAQs)
• To show you how the Internet really works
• To teach you how to read Internet addresses
• To do all of this in ENGLISH!!
What IS the Internet?What IS the Internet?
“A network of networks based on the TCP/IP protocols, a community of people who use and develop these protocols, and a collection of resources that can be reached from those networks.”
-- Krol & Hoffman