1. Voice Over Internet
Protocol
Presented by :
A.S.Warnakulasuriya
[Eng/14/092]

2. Outline
• What is Voice over Internet Protocol (VoIP) ?
• History
• What is internet Protocol?
• How VoIP works?
• Different ways to establish a VoIP connection
• VoIP Protocols
• Applications of VoIP
• Medial Applications of VoIP
• Advantages and Disadvantages

3. What is VoIP?
A method of converting analog audio signals to digital data
packets (IP packets) that can be transmitted over the internet
(via Internet Protocol) rather than via the Public Switched
Telephone Network (PSTN).
Internet
Voice IP PacketsDigital signals

4. Voice Digital signals
What Happens in Traditional
Voice calls?

5. VoIP….
Also known as,
• Internet telephony
• Broadband telephony
• Broadband phone service
supports real-time full-duplex digital voice over the Internet
Possible to make either PC to PC call, PC to telephone calls
or telephone to telephone calls using VoIP
However, in the world today, it is used not only to make
phone calls but for general communications over the
internet. Example : Fax, Video, Files

6. Brief History
 VoIP started with a company called “VocalTec” in 1995.
• They pioneered the first widely available Internet phone which was called
the “Internet Phone”.
• It allowed one Internet user to call another
• No video was available at the time, and the setup required that both
users be on the same Operating system.
 In 1996, Internet voicemail applications came to life.
• Users could send voicemails over the Internet to the destination phone.
Complications : poor sound quality, periods of silence due to
packet loss, and frequent loss of connection.

7. VocalTec Internet phone 1995

8.  In 1998, VocalTec went on to create computer-to-telephone, and
telephone-to-telephone calling capacities for VoIP.
• Unsuccessful --- VoIP calls accounted for less than 1% of all voice calls.
• Reasons: though the calls were free, the caller had to listen to a series of
advertisements before continuing as well as after finishing a conversation.
 In 2003, three different companies introduced VoIP switching
software as standard add-ons in their routing equipment.
• The number of VoIP calls leapt significantly to 25% of all voice calls.
The availability of broadband Ethernet service meant that call
quality improved significantly, and connectivity was much less of
a problem than it was with poorer, dial-up connections.
Today VoIP communication accounts for 68% of all voice calls.

9. What is Internet protocol?
• The principal communication
method (or protocol) by
which data is sent from one
host (computer, smartphone
etc.) to another host through
the Internet.
• A host on the Internet has at
least one IP address that
uniquely identifies it from all
other connected devices on the
Internet.
• Protocol is a set of rules
governing the format of data
(sent over the Internet)

10. Protocol Layering
Voice Data (1000 bytes)
TCP Header
(20 bytes)
IP Header
(20 bytes)
Typical IP Datagram used for VoIP Communications
Physical Transport (e.g, Cable Modem)
IP (Internet Protocol)
TCP UDP
Applications

11. Why VoIP is so popular?
• Internet is now available most part of the world
• Existing standard internet connection can be easily modified
to utilize VoIP communications
• Free or cheaper than a traditional voice communication
• VoIP technology allows the user to integrate voice and data
at the same time using a private data network
• Reducing the overall maintenance cost for the voice and
internet facilities

12. Making rules for VOIP
IETF (INTERNET ENGINEERING TASK FORCE)
This community of engineers that standardizes the
protocol that defines how the internet and internet
protocol work
ITU ( INTERNATIONAL TELECOMMUNICATION UNION)
An international organization where government &
private sector coordinate global telecom network and
services

13. How VoIP Works?

14. How PSTN Works?
1. Signaling the user telephone at the other end
2. Channel setup between two telephones
3. Encoding the analog (voice) signals into digital
signals
4. Transmitting the digital signals over a circuit-
switched network

15. How VoIP call Works?
1. Signaling the user telephone at the other end
2. Channel setup between two telephones
3. Digitization of analog (voice) signals
4. Encoded digital information is packetized
5. Transmitting the IP packets over a packet-switched network
(Internet).

16. If IP phone
Simplified Network Diagram of VoIP
Switch

17. Different ways to Use VoIP?
The most interesting thing about VoIP is that there is
not just one way to place a call. In fact, there are three
distinctive ways to make a call by using VoIP
technology.
1. Using a ATA
2. Using IP Phones
3. Using softphone

18. 1. Using a ATA
• Most simplest and common way to use VoIP facility
• ATA stands for “Analog Telephone Adapter”
• Basically an analog to digital converter which has the
added capability to packetize digital data
• ATA allows the user to connect a standard phone to
his/her Internet connection

19. An Analog Telephone
Adapter
Ports of Analog Telephone
Adapter

20. 2. Using IP Phones
• Specialized phones look just like normal phones with a
handset, cradle and buttons.
• Instead of having the standard RJ-11 phone connectors, IP
phones have an RJ-45 Ethernet connector.
• IP phones connect directly to the router of the user and have all
the hardware and software necessary right onboard to handle
the IP call including an inbuilt analog to digital convertor.

21. RJ45 Ethernet Connector RJ11 telephone Connector

22. IP Phone

23. 3. Using softphone
• Softphone is an application software installed on a networked
computer
• Helps in making VoIP communication between two computers.
• Easiest way to use VoIP
• The user does not even have to pay for long-distance calls
(international calls)
• Requirements to establish a connection:
 VoIP application software
 a microphone to input sound
 speakers to output sound,
 a sound card
 Internet connection.

24. • Except for the internet usage (in terms of data usage), the calls
are completely free of charge.
Internet

25. • Famous softphone VoIP providers ;

26. VoIP Protocols
• A standard used to define a method of exchanging data over a
computer network (such as local area network) in order to
provide efficient VoIP services.
• Each protocol has its own method of :
how data is formatted when sent
what to do with it once received
how that data is compressed
how to check for errors in data.
• Some of these protocols are based on open standards
(example: H.323 protocol)
• Some are proprietary protocols (example: Skype protocol).

27. Some of the most common protocols used in
VoIP.
• H.323 Protocol
• Media Gateway Control Protocol (MGCP)
• Session Initiation Protocol (SIP)
• H.248 Protocol
• Real-time Transport Protocol (RTP)
• RTP Control Protocol (RTCP)
• Secure Real-time Transport Protocol (SRTP)
• Session Description Protocol (SDP)
• Inter-Asterisk eXchange (IAX)
• Jingle XMPP
• Skype protocol

28. Applications of VoIP
1. As the main voice and data communication medium in
Organizations
2. Video conferencing
3. Cloud-based VoIP service can provide bandwidth
utilization information that allows you to view data
usage over a period of time
 Inbound and outbound call detail reports let you view details of your
company's call history, including rate centers, duration, originator,
destination, and cost.

29. 4. As a Coaching tool.
In employee training instead of giving them advice after
they've hung up the phone with the client, with VoIP the
trainer can give them advice while they're on the call
without the client noticing.
5. FoIP (Fax over Internet Protocol). It is an alternative IP-
based solution for delivering fax over the internet.
6. Medical Applications

30. Medical Applications of VoIP
• Voice over Internet Protocol (VoIP) is taking communications to new
heights as never before and hospitals and the healthcare sector all
across the world seem to be jumping on board. From full-fledged
hospitals to small clinics and health care offices, VoIP is changing
the way the medical world stays connected.
• VoIP in Healthcare basically involves transmitting healthcare
services and information between physicians or other medical staff
by means of VoIP services.
• VoIP can be readily utilized to enhance modern healthcare services
between and within major hospitals.

31. 1. Performing Long distant Operations
(Telemedicine)
Most pressing healthcare issues that VoIP can resolve reside in rural areas.
In regions where there is
little prevalence of technology,
less prevalence of experienced medical practitioners
healthcare quality can be very poor.
In situations that necessitate immediate surgery or other complicated
procedures, rural patients may not have access to adequately trained or
experienced professionals.
In these cases, VoIP can be, literally, a lifesaver. With a simple video call
over a secure connection, skilled doctors can impart invaluable
procedural expertise on rural practitioners, allowing them to perform vital
and complex operations from hundreds, even thousands of miles away.

32. Long Distance Surgery

33. 2. To process patient calls
• “We were missing a lot of calls, and people weren’t able to get
access to health care,”
- David Mendenhall in 2014–
(Chief technology officer at the healthcare network, USA.)
• By utilizing VoIP and contact center services, hospitals and
doctors’ offices can process multiple calls at the same time and
sort them on a priority basis.
• ensure that incoming calls are answered in a timely manner.
• Makes it easier for patients to pay their outstanding balances over
the phones, as each person can be identified by their name and
account information.

34. 3. Reduce Service Costs
• “U.S. hospitals waste more than $12 billion annually on
communications inefficiency.”
- Healthcare Management Society, USA -
• Hospitals and clinics are expensive to run and most medical
organizations are currently experiencing a period of budgetary
cutbacks.
• Cloud-based business communications allow hospitals
to improve their connections with patients and other hospital
staff while reducing the service costs.
• Eliminate the need to maintain a dedicated phone line, thus
eliminating separate maintenance and service fees.

35. 4. No installation down time and very
small Repair down time
• Hospitals don't have a lot of down time. VoIP systems are
installed over existing computer networks, which means
the installation process is fast.
• Involves no disruptive installation procedures like running
wires or installing huge hardware.
• Breakdown or malfunction is very rare hence
breakdown/repair downtime will be less

36. 5. RoboDoctor Concept
Internet

37. “The future of medicine is one where there is
better sharing of medical and patient data, and
VoIP is a part of that because the ability to
easily communicate is part of this future”
Prof. Ritu Agarwal
University of Maryland and director of the Center for Health
Information and Decisions Systems
Future of Medicine and VoIP’s part in it

38. Advantages of VoIP
• The main advantage of VoIP service is the cost. They are either very cheap or
absolutely free of charge. Therefore most part of the population can afford them.
• It is also a one stop solution to many day-to-day activities of general public.
With VoIP one can chat, send files, share pictures, videos, and talk, make
conference calls, and make video calls and even video conferences. So it is a one
stop solution with fewer fees to pay.
• VoIP is all about the user easiness. You do not have to buy and install any large
complex equipment. If you have internet connection in your home all you need is
VoIP software. Install it and then start making calls.
• As mentioned throughout the paper, VoIP service reduce the maintenance
cost as the internet connection and telephone system are not two separate
entities any longer.
• Not only voice but also video conferencing is also possible. Not only that fax
can also be sent over the VoIP network.

39. • Less reliable than the traditional switched circuit method of telephone
communications. This is because some data packets that the voice is sent in
can be lost resulting in a small bit of jittering and low sound quality.
• Another drawback of VoIP is it is internet-speed dependent. If the
network is congested or is having a very low speed the communication
cannot be able to be established easily. Even if the communication is
established between two hosts, the reliability of the call will again be an
issue.
• Furthermore, if the allocated data bundle of the internet connection of
the user has exceeded for the month, then he/she will not be able to make
a call or establish any form of IP based communication no matter how
urgent the situation may be.
Disadvantages of VoIP

40. References
• Groff, A., 2015. Healthcare Global. [Online]
Available at: http://www.healthcareglobal.com/hospitals/1774/5-Ways-VoIP-Can-Help-Hospitals-
Minimize-Communication-Costs
[Accessed 24 April 2016].
• Unuth, N., 2014. About Tech. [Online]
Available at: http://voip.about.com/od/voipbasics/a/whatisvoip.htm
[Accessed 24 April 2016].
• Cox, J., 2010. Network World. [Online]
Available at: http://www.networkworld.com/article/2244381/wireless/wireless-voip-benefits-
being-frustrated-in-healthcare--study.html
[Accessed 24 April 2016].
• Anon., n.d. Federal Communications Commission. [Online]
Available at: https://www.fcc.gov/general/voice-over-internet-protocol-voip
[Accessed 24 April 2016].
• Anon., n.d. iPRIMUS. [Online]
Available at: http://www.iprimus.com.au/products/voip/what-is-voip/
[Accessed 24 April 2016].

41. Thank You!!!