Internetwork - A. How did The Internet get started? What was the ARPA-NET? UCLA Computer Network (1969) SRI-Stanford (1969) internetwork

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1 Tpics internetwrk Internetwrk - A CSIT100 internet The Internet Intranet Extranet VPN 3 Hw did The Internet get started? 1957: The Russians launched the first satellite 1957: American respnse: imprve science and technical infrastructure What was the ARPA-NET? The first Cmputer Netwrk that cnnected (2/4) cmputers in (2/4) US universities. Advanced Research Prjects Agency (ARPA) 1969: ARPA-NET was created as result f the ARPA prject 4 5 UCLA Cmputer Netwrk (1969) UCLA SRI-Stanfrd (1969) UCLA SRI 1 nde: Aug. 30, nde: Oct. 1, 1969 IMP=Interface message prcessr 6 7 1

2 Internet the first steps Cmputer Netwrk (1969) Lenard Kleinrck, a prfessr f cmputer science at the University f Califrnia-Ls Angeles. and frankly, all we wanted t d was lg in -- t type an l--g, and the remte time-sharing system knws what yu're trying t d. S we typed the "l," and we asked ver the phne, "Did yu get the 'l?' " And the respnse came back, "Yep, we gt the 'l.' " We typed the "." "Gt the '?' " 'Yep, gt the '.' " Typed the 'g.' "Yu get the 'g?' " Crash! SRI's hst crashed at that pint. S the very first message ever n the Internet was the very simple, very prphetic "l," as in l and behld. (Sept. 1969) And, yu knw, we weren't aware that this was a significant event that wuld be recrded in histry. 8 UCLA Stanfrd Research Institute UTAH UCSB 4 ndes: Dec 5, The first Internet cnnectin, with UCLA's Lenard Kleinrck The details (discussin with Lenard Kleinrck) (see the first ruter) Nde 1: UCLA (30 August, hked up 2 September) Functin: Netwrk Measurement Center System, OS: SDS SIGMA 7, SEX Nde 2: Stanfrd Research Institute (SRI) (1 Octber) Netwrk Infrmatin Center (NIC) SDS940/Genie Dug Engelbart's prject n "Augmentatin f Human Intellect" Nde 3: University f Califrnia Santa Barbara (UCSB) (1 Nvember) Culler- Fried Interactive Mathematics IBM 360/75, OS/MVT Nde 4: University f Utah (December) Graphics DEC PDP-10, Tenex Lenard Kleinrck The Internet tday (descriptin f first internet)

3 What is a Cmputer Netwrk? Cmputer Netwrk is a cllectin f cmputers cnnected tgether with Links Internet? At the beginning, the cmputer netwrk cnnectin f tw r mre cmputers had the name: internetwrk r internet (i - lwercase) As the internet expanded t a huge netwrk t cver the whle planet a new name was given t the cmputer netwrk The Internet (I Uppercase) Links: Wired and Wireless Internetwrk = netwrk f netwrks Hw big is the Internet? 1980: The Internet had nly 200 cmputers 1995: The Internet had 1 millin cmputers 1998: The Internet had 2.5 millin cmputers 2000: 10 millin cmputers 2012: 12 billin devices cnnected t internet What is the Intranet? A private cmputer netwrk (LAN) within an rganizatin, having Internet-based capabilities What is the Extranet? Sme cmpanies pen their intranets t their cllabrating labs, cmpanies This new netwrk is called Extranet. VPN Virtual Private Netwrk. Is a private netwrk that uses a public telecmmunicatin netwrk (Internet) t allw remte users and sites t cnnect tgether. VPN s are mre secure, cheaper than dedicated lines. Access t VPN s is usually by invitatin

4 VPN VPN services Tp VPN CyberGhst (cyberghstvpn.cm) Free Private Internet Access (privateinternetaccess.cm) TrGuard (trguard.net) Article reviewing VPN privacy Wh can access the Internet? Everyne with a persnal cmputer and a MDeM and Then what d we need in rder t cnnect a cmputer with the Internet? Get in tuch with an Internet Service Prvider (ISP): Verizn, Cmcast, Cablevisin ISP are cmpanies that charge users t access the Internet. Telephne wires, r Cable TV wires, r Air (Wireless) ISP t reginal ISP The Internet Reginal ISP Lcal ISP

5 Free Internet? Free Internet 0.0 (zer.zer) $ Wh wns the Internet? N ne really wns the Internet Gvernments, schls, cmpanies, etc wn pieces f the infrastructure There are rganizatins that versee and standardize the netwrk: NSF, Internet Engineering Task Frce, ICANN Cmputer cmmunicatin First f all, cmputers must speak the same language just like humans speak the same language t cmmunicate. Cmputers use a standard language that allws different cmputer netwrks and cmputers t talk t each ther. This standard language is knwn as TCP/IP What is the TCP/IP? Tw parts TCP and IP TCP/IP (Transmissin Cntrl Prtcl/ Internet Prtcl) is a standard way f packaging and addressing cmputer data (electric signals).. as they are shipped next dr r arund the wrld and arrive almst instantly withut being damaged r lst. (Cmputers n the Internet have special prgrams that allw them t speak in TCP/IP). [Prtcl is a cllectin f rules]

6 The TCP/IP details IP (Internet Prtcl) Respnsible fr addressing cmputers and sending packets between them Desn t guarantee delivery f a packet TCP/IP TCP (Transmissin Cntrl Prtcl) Divides data int packets Uses IP t send them Resembles them and checks fr errrs If sme packets didn t make it, they are resent TCP/IP is free, pen and easy t implement What is what yu can d with It is a facility similar with the Pstal-Mail but delivers characters r files (text, images, and speech) anywhere in the wrld. It takes anywhere frm a few secnds t a few minutes t deliver the characters r files tw parts Lcal & Dmain Lcal Dmain name mail.mntclair.edu

7 Send and receive User: receive with... POP3, IMAP4, http prtcls User: send with SMTP prtcl Mail servers: send and receive with SMTP prtcl Mail servers: Send and receive via SMTP All Mail-Servers in rder t exchange (send and receive) messages use: SMTP (Simple Mail Transfer Prtcl) SMTP is the standard prtcl fr sending s acrss the Internet. SMTP uses TCP-prt 25. Prt: A cmmunicatin channel, in cmputer netwrks, using the TCP Yur cmputer has 65,536 prts (2^16) The user can receive with.. POP3 (Pst Office Prtcl; versin-3) IMAP4 (Internet Mail Access Prtcl-4) HTTP (Web-based) The user can send with SMTP (Simple Mail Transfer Prtcl) Fr example: Micrsft Outlk Express, MS Outlk, Mzilla Thunderbird and Eudra, use POP3 r IMAP POP3 and IMAP4 prtcls POP3 (Pst Office Prtcl-3) The messages are stred in a cmputer until they are dwnladed t ur hard disk Dwnladed s are deleted frm the server The dwnladed messages can be read even when we are ffline IMAP4 (Internet Mail Access Prtcl-4) IMAP stres all the mail n the server Only cpies f messages are dwnladed t ur hard disk The Mail messages can be manipulated and rearranged n the server POP3/IMAP4/HTTP and SMTP Incming and Outging mail prtcls use different prts

8 POP3/IMAP4/HTTP use different prts Incming mail POP3 - prt 110 IMAP - prt 143 HTTP - prt 80 Secure IMAP (IMAP4-SSL) prt 585 Secure POP3 (SSL-POP) - prt 995 Outging mail SMTP prt 25 Secure SMTP (SSMTP) - prt 465 Scan yur cmputer s prts security ShieldsUp! AuditMyPC Firewall Test Free Internet Security Testing PC Flank Prtcls POP3 IMAP Web-based Web-based HTTP (Hyper Text Transfer Prtcl)

9 Yu can use e.mail t: Send (ASCII) text- based messages html files Ntepad files Send binary files jpg mp3 Send messages and files t multiple recipients Reply r t frward messages yu received etiquette and curtesy D nt send anything via that yu wuld nt want t read in yur hmetwn newspaper Yu cannt cntrl when yur message will be delivered. Thus, always assume that yur message will arrive at the wrst pssible time & chat emticns Text message abbreviatins Hw can yu access the MSU webmail? MSU

10 Cc: - Bcc: - attachments Passwrd: DO s & DON Ts Cc: Carbn Cpy (The address will be visible t thers) Bcc: Blind Carbn Cpy (The address is nt visible t thers) Attachment t an can be: Dcument, Image, Vice file Passwrd: DO s Passwrd: DON Ts Select a passwrd that is at least eight characters Use bth numbers and letters Select a passwrd that yu can remember Dn t select a passwrd that can be fund in a dictinary Dn t use yur name, nickname, names f friends as passwrds Change passwrd every mnth Passwrd: DO s & DON Ts Passwrd security levels High level Lw level Select a passwrd that is at least eight characters Dn t select a passwrd that can be fund in a dictinary Use bth numbers and letters Dn t use yur name, nickname, names f friends as passwrds Select a passwrd that yu can remember Change passwrd every mnth

11 Lw security High security Bth lw and high security Check strength f passwrd T crack a passwrd Gd Passwrd Class F attack; super cmputer ding 1,000,000,000 passwrds/sec attack