Internet telephony allows users to make voice calls over the Internet. It works by digitizing voice data and transmitting it as packets over the Internet using IP protocols. As technology has advanced, internet telephony offers high quality voice calls at low costs by combining traditional telephone networks with data networks.

1. SHREEJEE INSTITUTE OF
TECHNOLOGY AND MANAGEMENT
Internet Telephony
• Guided By:- Mr. Prakash
Singh Panwar
• By:- Abhishek Mahajan
• EC BRANCH 1ST YEAR

2. INTRODUCTION
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

3. The factors which are 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.

4. How internet telephony works?
In one side gateway connects to the telephone
word. It can communicate with any phone in the
world.
On the other side, the gateway connects to the
Internet world. It can communicate with any
computer in the world.
The gateway takes the standard telephone signal,
digitizes it, compresses it, packetizes it for the
Internet using IP protocol and routes it the
destination over the Internet.

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. INTERNET PROTOCOLS
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. Public switched telephone network
(PSTN)
• 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. WHAT AN IDEAL INTERNET TELEPHONY
• 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

10. INTERNET TELEPHONY HARDWARE
REQUIREMENT
• 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

11. ADVANTAGES
• 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.

12. DISADVANTAGE
• 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.

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

14. IMPACT ON THE IT MARKET
• 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.

15. INDIAN DIASPORA
• 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.

16. SUMMARY
• 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