Basic Network (the Internet) Applications Kittiphan Techakittiroj engktc@au.ac.th

Agenda Telnet: using other computer ftp: transfer files e-mail: send message world wide web: information retrieval

Telnet connect to server machine local machine act as “terminal text based communication transmit only “text” GUI is possible through terminal emulation simple implementation

What does it need to work? Telnet What does it need to work? Host name hostname.domainname au1.au.ac.th cwsysf.cwru.edu whitehouse.org domainname = localname.globalname purpose, e.g. edu, org, gov, net, mil country, e.g. th, us, jp, tw, be, tv, to account or permission identification = userid+password

Example: most TCP/IP implementation Telnet Example: most TCP/IP implementation au1% telnet btl4.eng.au.edu Trying 168.120.18.173... Connected to btl4.eng.au.edu. Escape character is '^]'. [SSL not available] Welcome to Linux 2.0.34. btl4 login: admin Password: ******* Linux 2.0.34. Last login: Wed May 5 10:40:17 on ttyp0 from 168.120.18.73. No mail. btl4:~$

Telnet Terminal Emulator improving “user interface” of telnet by terminal Emulator (Dump Terminal) ANSI IBM 3270 VT100/102 (most popular) VT240/340 (graphics enhancement)

Telnet: Terminal Emulator Example: MS Windows Telnet

E-mail Electronics mail transfer information from one to the other act as postal mail batch processing or off-line communication text based communication transmit only “text” binary (graphics, sound) need encoding

What does it need to work? E-mail What does it need to work? access to E-mail system mail-reader to receive mails mail-composer to send mails destination = name+’@’+address engktc@au.ac.th kxt15@po.cwru.edu information or data text binary need encoding before send and decoding after

Example: UNIX mail (get) E-mail Example: UNIX mail (get) hostname:~$ mail Mail version 8.1 6/6/93. Type ? for help. "/var/spool/mail/admin": 5 messages 1 new 1 anderson@meridian.co Mon Mar 8 15:56 77/3907 "OPNET News: LOCKHEED " 2 marlyn@rc.bel.alcate Mon Apr 12 14:49 98/2622 "work = money?" 3 JDCTechTips@sun.com Wed Apr 14 21:02 307/10179 "JDC Tech Tips No." 4 EActor@westnetinc.co Fri Apr 30 00:21 576/42551 "Re: About Your Course" >N 5 admin@btl4.eng.au.ed Wed May 5 11:19 14/424 "test" & 5 Message 5: From admin@btl4.eng.au.edu Wed May 5 11:19:30 1999 Date: Wed, 5 May 1999 11:19:30 +0700 From: Administrator <admin@btl4.eng.au.edu> To: admin@btl4.eng.au.edu Subject: test Cc: engktc@au.ac.th test of E-mail system on "btl4.eng.au.edu" & q Saved 1 message in mbox Held 4 messages in /var/spool/mail/admin hostname:~$

Example: UNIX mail (send) E-mail Example: UNIX mail (send) hostname:~$ mail admin@btl4.eng.au.edu Subject: test 2 this is the second test . Cc: hostname:~$ mail Mail version 8.1 6/6/93. Type ? for help. "/var/spool/mail/admin": 2 messages 1 unread 1 EActor@westnetinc.co Fri Apr 30 00:21 576/42551 "Re: About Your Course" >U 2 admin@btl4.eng.au.ed Wed May 5 11:23 14/423 "test 2" & 2 Message 2: From admin@btl4.eng.au.edu Wed May 5 11:23:36 1999 Date: Wed, 5 May 1999 11:23:36 +0700 From: Administrator <admin@btl4.eng.au.edu> To: admin@btl4.eng.au.edu & q Saved 1 message in mbox Held 1 message in /var/spool/mail/admin hostname:~$

Example: Netscape Messenger (get) E-mail Example: Netscape Messenger (get)

Example: Netscape Messenger (send) E-mail Example: Netscape Messenger (send)

FTP File Transfer Protocol sharing files via network transfer information from one to the other transfer files between remote host (server) and local host (client) file = information large or small text or binary

What does it need to work? FTP What does it need to work? Hostname: server location hostname.domainname au1.au.ac.th cwsysf.cwru.edu ftp.whitehouse.org account or permission identification = userid+password specific access public access file location: directory and name

Example: most TCP/IP implementation FTP Example: most TCP/IP implementation btl4:~$ ftp btl4.eng.au.edu Connected to btl4.eng.au.edu. 220 btl4.eng.au.edu FTP server (Version wu-2.4.2-academ [BETA-15](1) Wed May 20 1 3:45:04 CDT 1998) ready. Name (btl4.eng.au.edu:admin): admin 331 Password required for admin. Password: ******* 230 User admin logged in. Remote system type is UNIX. Using binary mode to transfer files. ftp> get /etc/hosts ./hosts local: ./hosts remote: /etc/hosts 200 PORT command successful. 150 Opening BINARY mode data connection for /etc/hosts (621 bytes). 226 Transfer complete. 621 bytes received in 0.089 secs (6.8 Kbytes/sec) ftp> quit 221 Goodbye

FTP Example: ws_ftp

WWW World Wide Web huge information systems: (text, graphics, audio, video, etc.) in hyper-text and hyper-media format allow the use of “telnet”, “ftp”, “e-mail” need to know only the location URL://location http://www.eng.au.edu/ ftp://ftp.au.ac.th/

Example: Lynx WWW GABAC School of Engineering (p1 of 3) Home History [INLINE] Announcement Academic Society Departments Programs Admission Facilities & Services Welcome to the Faculty of Engineering Assumption University of Thailand Hot News [INLINE] M.Eng. Application period!! click here for more information. [INLINE] Engineering Day is coming click here for more information. A Principle Objective of the Faculty of Engineering is To Develop Engineers who have Academic and Hands On Experience in the Most Recent Technologies. -- press space for next page -- Arrow keys: Up and Down to move. Right to follow a link; Left to go back. H)elp O)ptions P)rint G)o M)ain screen Q)uit /=search [delete]=history list

WWW Example: Neoplanet

WWW Example: Netscape