This document provides an overview of internet telephony (also known as voice over internet protocol or VoIP). It discusses how VoIP works by sending audio over the internet in real-time between computer users. The document also outlines the key factors and protocols that enable VoIP, including improvements in compression techniques, full-duplex sound cards, more powerful PCs, and protocols like SIP, RTP, and H.323. Both advantages and disadvantages of VoIP are presented, such as lower long distance costs but also potential issues with internet integration and latency.

1. A
PRESENTATION
ON
INTERNET TELEPHONY
GUIDEED BY R.K.DALAI
PRESENTED BY
LALITA
BEHURA
Reg. No-0305247037
Roll No-41

2. “It's probably the most significant
shift in the entire history of modern
communications, since the invention
of the telephone.”

3. IINNTTRROODDUUCCTTIIOONN
Internet telephony is a powerful and economical
communication option by combination of the
telephone network and data networks.
Internet telephony uses internet to send audio
between two or more computer users in the real
time,so the the user can converse vocal Tec
introduced the first internet telephony software
product in early 1995

4. THE FACTORS WHICH IS MAKING
INTERNET TELEPHONY POSSIBLE
 voice quality is increasing thanks to new
codec technology.
 There are on going improvements in
compression techniques.
 Full-duplex PC sound cards enable two way
simultaneous calls.
 The typical PC is getting more & more
powerful,making it possible processor-intensive
functions without specialized
hardware.

5. GENERATION OF INTERNET
TELEPHONY
The first generation :-Introduction to enable voice
conversations user with telephony software-equipped-
computers.
The second generation:-it overcomes the
difficulties with PSTN interfaces protocols and
mapping IP address.
The third generation:-internet telephony starts to
receive serious attention.these gateways provides a
two-ways interfaces between the PSTN and
internet.

6. IINNTTEERRNNEETT PPRROOTTOOCCOOLLSS
IP packets are forwarded across the network by routers
IP Routers do best-effort routing
Voice signals can be prioritized using priority queues
RTP and RTCP keep end points informed of
transmission quality.
Call set up is done using Session Initiation Protocol
(SIP) or something similar

7. VOICE OVER INTERNET
TELEPHONE
VoIP tries to let go voice (mainly human)
through IP packets.
 VoIP works like that, digitalizing voice in
data packets.
 Voice (source) - - ADC - - - - Internet - - -
DAC - - Voice (dest)

8. PPuubblliicc sswwiittcchheedd tteelleepphhoonnee
nneettwwoorrkk ((PPSSTTNN))
A synonym for traditional circuit-switched
telephone networks offered by public
telecommunication operators (PTOs), as
well as integrated services digital networks
(ISDN), and public land mobile networks
(PLMN).

9. PPSSTTNN vvss.. IInntteerrnneett TTeelleepphhoonnyy
Signaling & Media Signaling & Media
Signaling Signaling
Media
PSTN:
Internet
telephony:
China
Belgian customer,
currently visiting US
Australia

10. WWHHAATT AANN IIDDEEAALL IINNTTEERRNNEETT
TTEELLEEPPHHOONNYY
High volume call processing within and
between public and private networks.
High volume real-time translation between
IP and switched networks.
Economic scalability.
Broad acceptance and implementations of
standards.

11. TTHHEE IIPP TTEELLEEPPHHOONNYY AARRCCHHIITTEECCTTUURREE
CALL PROCESSING
LINE SWITCHING
CONNECTION
TRUNK
CONNECTION
IIPP PPHHOONNEE
SSOOFFTTPPHHOONNEE
CCLLIIEENNTT
MMCCSS 77880000
SSEERRIIEESS
EETTHHEERRNNEETT
LLAANN SSWWIITTCCHH
RROOUUTTEERR
GGAARRTTWWAAYY

12. MMAAJJOORR VVOOIIPP PPRROOTTOOCCOOLL
 Three major voip protocol are
1) 1.H.323
2) 2.SIP
3) 3.MGCP

13. FFuullllyy MMeesshheedd TTDDMM NNeettwwoorrkk
HH..332233
Tokyo
Sydney
London
New York
Frankfurt
Los Angeles
Amsterdam
Based on actual and world composites figures from Band-X, 4/01

14. MGC MGC
SIP
Server
ISUP ISUP
TGW TGW
PSTN PSTN
IP Network
SIP-T
SIP-T
SIP-T
MGC – Media Gateway Controller
TGW – Trunking Gateway
PSTN – Public Switched Telephone
Network
MEGACO/H.248
Signaling
SSIIPP--TT User Data

15. MGC – Media Gateway Controller
MG – Media Gateway
PSTN – Public Switched Telephone Network
MGC MGC
IP backbone
MG MG
MEGACO
MEGACO/H.248
Signaling
MMEEGGAACCOO User Data
Private
Network
Private
Network
SIP, H.323,
RTP, AAL 1/2/5

16. INTERNET TTEELLEEPPHHOONNYY HHAARRDDWWAARREE
RREEQQUUIIRREEMMEENNTT
PC 386 or more & Sound card.
 Full duplex capable .
 A network card connected with internet.
 Hardware accelerating cards .
 Quicknet PhoneJack
 Quicknet LineJack
 VoiceTronix V4PCI
 VoiceTronix VPB4
 VoiceTronix VPB8L

17. AADDVVAANNTTAAGGEESS::
In VoIP mechanism you can talk all the time
with every person you want (the needed is
that other person is also connected to
Internet at the same time), as far as you want
(money independent) and, in addition, you
can talk with many people at the same time.
Exchange audio data with people and also
simultaneously sending images, graphs and
videos.

18. DDIISSAADDVVAANNTTAAGGEE
Integration between VoIP architecture and
Internet.
voice data communication must be a real
time stream (you couldn't speak, wait for
many seconds, then hear other side
answering): this is in contrast with the Internet
Heterogeneous architecture that can be made
of many routers (machines that route
packets),which has a very high round trip time
(RTT), so we need to modify something to get
it properly working.

19. WHAT THE USER GET NOW
Point to multipoint voice.
Data conferencing.
Application sharing.
Long distance telephone saving.

20. IIMMPPAACCTT OONN TTHHEE IITT MMAARRKKEETT
Will IP Telephony be able to cut cost?
Ans:-It depends on the organistions ability
to reduce the costs associated with infotech
personnel,network equipment and the
transmission services.

21. IINNDDIIAANN DDIIAASSPPOORRAA
In Indian context we need to cut the costs
for the people to be enabled to connected to
the world and change the living styles.

22. SSUUMMMMAARRYY
Business acceleration in this century is
directly related to the success of IT
organization's ability of giving a
competitive edge
“Convergence of all communication traffic
onto a packet network “

23. QQ--AA
??????????

24. ""AAllwwaayyss ddoo rriigghhtt.. TThhiiss wwiillll ggrraattiiffyy
ssoommee ppeeooppllee aanndd aassttoonniisshh tthhee
rreesstt..""
TTHHAANNKK YYOOUU