1. CS335 Networking & Network Administration Tuesday, June 1, 2010

2. IP telephony Equipment is less costly than telephone switches Backward compatible with PSTN (public switched telephone network) Be able to work with calls that originate with PSTN and terminate with IP telephone and vice versa

3. Encoding Audio is encoded using Pulse Code Modulation (PCM) The digitized audio is transferred using Real- Time Transport Protocol (RTP) – RTP solves some of the problems of duplication, jitter, and out of order delivery Each RTP message is encapsulated in UDP datagram, which is further encapsulated in IP datagram

4. Basic IP telephone system IP telephone Media Gateway Controller

5. Interoperation Media Gateway Signaling gateway

6. SIP – Session Initiation Protocol Operates at application layer Encompasses all aspects of signaling, including location of a called party, notification and setup (ringing a phone), determination of availability, and termination Provides services such as call forwarding Relies on multicast for conference calls Allows the two sides to negotiate capabilities and choose the media and parameters to be used

7. Example SIP session

8. IP telephones and electrical power Analog phones don’t need power IP telephones need power also Power over ethernet

9. FTP BSD UNIX

10. FTP Establish connection Authorize Put or Get files List files cd, cdup, ls

11. File types Binary Text Verbose and quiet mode

12. TFTP Trivial file transfer protocol Uses udp Devices use this to update software to devices like switches, routers, etc.

13. NSF - Network File System Accommodates applications that only need to read or write a part of a file Integrated into a computer’s file system http://www.uwsg.iu.edu/usail/network/nfs/over view.html http://www.uwsg.iu.edu/usail/network/nfs/over view.html http://www.faqs.org/rfcs/rfc1094.html http://www.tldp.org/LDP/nag/node140.html

14. WWW Browsing http https Html Xml Web caching

15. Dynamic Web CGI ASP JSP PHP Lasso Cold Fusion Java Javascript

16. RPC Remote Procedure Call Places procedures on more than one machine

17. RPC Remote

18. RPC Communication stubs – software to implement the RPC

19. Middleware ONC RPC CDE/RPC MSRPC CORBA MSRPC2 COM/DCOM JINI SOAP XML

20. RPC http://www.microsoft.com/technet/security/bul letin/MS04-012.mspx http://www.microsoft.com/technet/security/bul letin/MS04-012.mspx http://www.cs.cf.ac.uk/Dave/C/node33.html http://searchwebservices.techtarget.com/sDef inition/0,,sid26_gci214272,00.html http://searchwebservices.techtarget.com/sDef inition/0,,sid26_gci214272,00.html