1. Krerk Piromsopa. Application Protocols & System Services. 1 Krerk Piromsopa. Department of Computer Engineering. Chulalongkorn University.

2. Krerk Piromsopa. Application Protocols & System Services. 2 Application Protocols ECHO (#7) FINGER (#79) TELNET(#23) HTTP(#80) FTP (#20,#21) SMTP(#25) POP3 (#110)/ IMAP(#143) etc. TCP/UDP Binding with Port.

3. Krerk Piromsopa. Application Protocols & System Services. 3 Finger ksh-2.04$ telnet cpu200 finger Connected to cpu200.cp.eng.chula.ac.th. Escape character is '^]'. krerk Login Name TTY krerk Krerk Piromsopa pts/5 g41kpr Krerk Piromsopa pts/3 u38kpr Krerk Piromsopa pts/3 Use to verify user and view current logon user. TCP Port 79 Specify username, part of Name Return Login, Name, TTY, etc...

4. Krerk Piromsopa. Application Protocols & System Services. 4 HTTP HTTP/1.1 (RFC 2616) TCP Port # 80 Stateless Protocol Server Pull Protocol Message format –Request –Response Data format –MIME –Encoding http_URL = "http:" "//" host [ ":" port ] [ abs_path [ "?" query ]] Date format RFC 822, RFC 850, ANSI C

5. Krerk Piromsopa. Application Protocols & System Services. 5 HTTP Request Message GET /index.html HTTP/1.1 Host: www.cp.eng.chula.ac.th Connection: close User-agent: Mozilla/4.0 Accept-language:en Request Line Header Lines Entity Body Support Method : GET, POST, HEAD, PUT, DELETE, etc….

6. Krerk Piromsopa. Application Protocols & System Services. 6 HTTP Response Message HTTP/1.1 200 OK Date: Sun, 23 Jun 2002 14:56:35 GMT Server: Apache/1.3.19 (Unix) Last-Modified: Thu, 14 Mar 2002 07:39:11 GMT ETag: "1300d8-e1c-3c90539f" Accept-Ranges: bytes Content-Length: 3612 Content-Type: text/html ………… (data) Status Line Header Lines Entity body Common status code –200 OK, 400 Bad Request, 404, Not Found, 505 HTTP Versionot Supported.

7. Krerk Piromsopa. Application Protocols & System Services. 7 Web Data HTML Test Hello, world. CSS.normal { font-family: "MS Sans Serif", helvetica, Angsana; font- size: 14px; color: #000000}.dirlist { font-family: "MS Sans Serif", helvetica, Angsana, sans-serif; font-size: 14px; color: #CC0000}

8. Krerk Piromsopa. Application Protocols & System Services. 8 SMTP Protocol SMTP (RFC821) TCP Port # 25 PUSH Protocol Data format –MIME –Encoding Commands –HELO –MAIL FROM –RCPT TO –DATA –QUIT

9. Krerk Piromsopa. Application Protocols & System Services. 9 SMTP Sample 220 cpu200.cp.eng.chula.ac.th ESMTP Sendmail ….. HELO arctic 250 cpu200.cp.eng.chula.ac.th Hello arctic.cp.eng.chula.ac.th pleased to meet you MAIL FROM:krerk@cp.eng.chula.ac.th 250 krerk@cp.eng.chula.ac.th... Sender ok RCPT TO : krerk@cp.eng.chula.ac.th 250 krerk@cp.eng.chula.ac.th... Recipient ok DATA DATA 354 Enter mail, end with "." on a line by itself. 250 WAA10073 Message accepted for delivery QUIT 221 cpu200.cp.eng.chula.ac.th closing connection

10. Krerk Piromsopa. Application Protocols & System Services. 10 POP3 POP3 (RFC1939) TCP Port # 110 Command –user –pass –list –retr –dele –quit

11. Krerk Piromsopa. Application Protocols & System Services. 11 POP3 Sample +OK POP3 cpu200.cp.eng……. user krerk +OK User name accepted pass +OK Mailbox open, 2 messages list +OK Mailbox scan listing follows 1 498 2 498. retr 2 +OK 426 octets. dele 2 +OK Message deleted quit +OK Sayonara

12. Krerk Piromsopa. Application Protocols & System Services. 12 FTP FTP (RFC 959) TCP Port #20, # 21 Separate Control/Data Connection Common commands –USER –PASS –LIST –RETR –STOR

13. Krerk Piromsopa. Application Protocols & System Services. 13 FTP Sample 220 cpu.cp.eng.chula.ac.th FTP server ---> USER anonymous 331 Guest login ok Password: ---> PASS XXXX 230 Guest login ok, access restrictions apply. ---> SYST 215 UNIX Type: L8 Remote system type is UNIX. Using binary mode to transfer files. ---> PASV 227 Entering Passive Mode (161,200,93,1,220,154) ---> LIST 150 Opening ASCII mode data connection for directory listing. total 8 drwxrwxrwx 6 14 root 4096 Feb 18 2002 pub 226 Transfer complete. ftp> quit ---> QUIT 221 Thank you for using the FTP service on cpu.cp.eng.chula.ac.th.

14. Krerk Piromsopa. Application Protocols & System Services. 14 System Services Directory Services –DNS –LDAP –NIS –HESIOD –SAMBA File Services –NFS Printing Services –CUPS –LPR SAMBA

15. Krerk Piromsopa. Application Protocols & System Services. 15 DNS Perform Name service. UDP #53 Local name servers Root name servers Authoritative name server Record Type –Forward –Alias –MX –Reverse Caching mechanism CpuMX 20 cpu200 cpu200 A 161.200.93.11 www IN CNAME cpu 1.93.200.161.in-addr.arpa. IN PTR cpu.cp.eng.chula.ac.th.

16. Krerk Piromsopa. Application Protocols & System Services. 16 LDAP Lightweight Directory Access Protocol (X.500 Style) Distributed Database LDAP is a vendor-independent, open, network PROTOCOL standard and thus is as platform-independent as you can get

17. Krerk Piromsopa. Application Protocols & System Services. 17 RPC (Remote Procedure Call) When the client calls the remote procedure, it’s really calling a function the local host that’s generated by the RPC package. This function is called the client stub. The client stub packages the procedure arguments into a network message, and sends this message to the server. A server stub on the server host receives the network message. It takes the arguments from the network message, and calls the server procedure that the application programmer wrote When the server function returns, it returns to the server stub, which takes the return values, packages them into a network message and sends the message back to the client stub. The client stub takes the return values from the network message and returns to the client application.

18. Krerk Piromsopa. Application Protocols & System Services. 18 RPC (Cont.) UDP (or TCP) # 111 Format of call message. –transaction ID (client assigned) –call (0 for call) –RPC version –program # –version # –procedure # –credentials –verifier (Secure RPC) –parameter Format of reply message. –transaction ID –reply (1 for reply) –status (0 success) –verifier –accept status –results Related Application (Program) –port mapper(100000) –NFS (100003) –mount (100005) –lock manager(100021)

19. Krerk Piromsopa. Application Protocols & System Services. 19 NIS

20. Krerk Piromsopa. Application Protocols & System Services. 20 NFS

21. Krerk Piromsopa. Application Protocols & System Services. 21 LPR

22. Krerk Piromsopa. Application Protocols & System Services. 22 CUPS RFC 2911 The Common UNIX Printing System ("CUPS") is a cross- platform printing solution for all UNIX environments. It is based on the "Internet Printing Protocol" and provides complete printing services to most PostScript and raster printersInternet Printing Protocol

23. Krerk Piromsopa. Application Protocols & System Services. 23 SAMBA File & print services Authentication and Authorization Name resolution Service announcement (browsing)

24. Krerk Piromsopa. Application Protocols & System Services. 24 Reference RFC http://www.stanford.edu/~hodges/talks/mactivity.ldap.97/ http://www.samba.org/ http://www.pwg.org/ipp/