voip ppt(RAJAN)

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By: jacunn06 (14 month(s) ago)

please send this in ppt to jacunn06@louisville.edu. Thanks

By: dhrj2007 (14 month(s) ago)

plzz send me this ppt on dhrj2007@yahoo.com ....thanking u in advance

By: pritamsen (14 month(s) ago)

Thanks for downloading me this ppt.

By: naqqash_khalid (19 month(s) ago)

excellent work boy

By: Sarmadidrees (25 month(s) ago)

Mr Kumar it is a really concise and informative presentation thank you very much

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Presentation Transcript

SEMINAR TOPICON : 

SEMINAR TOPICON PRESENTED BY: RAJAN KUMAR 8th SEM(ENTC-A) REGD. NO:0501212311 3/20/2009 1

OUTLINE : 

OUTLINE INTRODUCTION WHAT IS VOIP? HISTORY PSTN Vs. VOIP MODES OF OPERATION OF VOIP BASIC PRINCIPLES OF VOIP HOW VOIP WORKS? ADVANTAGES LIMITATIONS APPLICATIONS CONCLUSION 3/20/2009 2

INTRODUCTION : 

INTRODUCTION The traditional method used for transmitting voice is PSTN. Now more and more communication is done in digital format and transported via data networks such as internet. As data traffic is much faster than telephone traffic, so we prefer to send voice over data networks. 3/20/2009 3

WHAT IS VOIP? : 

WHAT IS VOIP? Voice Over Internet protocol (VoIP) is a protocol used for the transmission of voice and fax phone calls through the Internet or other packet-switched networks. It is also called IP telephony, Internet telephony, voice over broadband, broadband telephony. 3/20/2009 4

HISTORY OF VOIP : 

HISTORY OF VOIP The commercial Voip software was introduced in 1995 by Vocaltec. Designed for home PC Uses H.323 Protocol 3/20/2009 5

PUBLIC SWITCHED TELEPHONE NETWORK : 

PUBLIC SWITCHED TELEPHONE NETWORK • POTS (Analog Telephony) It stands for Plain Old Telephone Service. Dedicated link between partners Reserved bandwidth • ISDN (Digital Telephony) It stands for Integrated Services Digital Network. On each link a channel is reserved Reserved bandwidth between partners 3/20/2009 6

Analog Telephony Digital Telephony 3/20/2009 7

PSTN vs. INTERNET : 

PSTN vs. INTERNET PSTN Voice networks use circuit switching. Dedicated path between calling and Called party. Bandwidth is reserved in advance. Cost is based on distance and time. INTERNET Data network use packet switching. No dedicated path between sender and receiver. It acquires and releases bandwidth, as it is needed. Cost is not dependent on time and distance. 3/20/2009 8

CIRCUIT SWITCHING PACKET SWITCHING 3/20/2009 9

MODES OF OPERATION : 

MODES OF OPERATION PC to PC PC to Phone Phone to Phone 3/20/2009 10

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Audio Codecs Data Transport (RTP, RTCP) Addressing Signaling (SIP, H.323) 3/20/2009 14 VOIP: BASIC TECHNIQUES

Slide 15: 

Here analog signal is converted into digital data. Three popular audio codecs :- G.711 G.723.1 G.729 Implemented using voice coders: Since voice contains lot of data, it is compressed by Vocoders without compromising the reliability and quality of voice signal. 3/20/2009 15 AUDIO CODECS:

3/20/2009 16 Translation of analog signal to digital signal

RTP It stands for Realtime Transport Protocol. Application layer protocol for transmitting real time data (audio, video, ...) Includes payload type identification, sequence numbering, time stamping, delivery monitoring. 3/20/2009 17 DATA TRANSPORT (RTP, RTCP)

RTCP : 

RTCP It stands for Realtime Transport Control Protocol. Main functions: support for multi-point communication Periodic transmission of control packets to all participants in the session. 3/20/2009 18

Here phone no. is converted to an IP address. Simple format addresing: <user | phone number>@<domain | hostname | IP address> 3/20/2009 19 ADDRESSING

Signaling in VOIP is needed for : Locating partners. Agreeing on port numbers for RTP / RTCP sessions. agreeing on coding / decoding procedures. Types of Signaling Protocols: H.323 SIP 3/20/2009 20 SIGNALING

H.323 : 

H.323 Recommendation published by ITU in 1996. It is designed to act above transport layer and is mainly used for transmission of voice, data and video conferencing over packet networks. 3/20/2009 21

SIP : 

SIP SIP stands for Session Initiation Protocol. Developed by IETF since 1999. It is an text-based application-layer control protocol for creating, modifying and terminating sessions with one or more participants. Sessions include Internet Multimedia conferences or Internet Telephone calls. 3/20/2009 22

How VoIP Works? : 

How VoIP Works? 3/20/2009 23

ADVANTAGES: : 

ADVANTAGES: Cheaper call rates Simplification High efficiency Calling person need not necessary to receive call. Better Voice Quality Using Wideband Codecs Adding new features and applications over time is easy. Integration of voice, data, fax, video is possible. 3/20/2009 24

Slide 25: 

3/20/2009 25

LIMITATIONS : 

LIMITATIONS Packet Delay Packet Loss (no guarantee of delivering packets) Jitter (variable delay) 3/20/2009 26

APPLICATONS : 

APPLICATONS Real time applications: Telephony ( two-way) Radio-TV Broadcast (one-way) Non-real time applications: e_mail OTHERS: Integration of data,voice and fax Video telephony Enhanced teleconferencing Used in Amateur Radio 3/20/2009 27

COMMERCIAL APPLICATIONS : 

COMMERCIAL APPLICATIONS 1: VONAGE founded in January 2001 about 130,000 customers 3/20/2009 28

3/20/2009 29 2: AT&T AT&T is rapidly evolving from a company that handles mostly long-distance voice calls to a company that provides data and voice communications over any distance. 3: INODE 4:TELEKOM AUSTRIA

CONCLUSION : 

CONCLUSION Like everything else, as the technology changes so at first only a few companies like Cisco and Lucent offered VoIP services, but the large telecommunications carriers – such as AT&T and Sprint -- are catching on . VoIP is predominately used for personal instead of enterprise-wide use. 3/20/2009 30 The availability of high-quality audio using wideband codecs, video conferencing, and document sharing enables more effective and pleasant communication.

3/20/2009 31 ELECTRONICS FOR YOU(VOLUME-37) Voip Fundamentals By Jonathan Davidson www.bestneo.com www.google.com www.wikipedia.com www.howstuffworks.com www.cisco.com www.seminartopics.com www.quintum.com www.tech-faq.com

3/20/2009 32 THANK U…

3/20/2009 33 QUERIES?