voip ppt final 1
Post on 03-Apr-2018
230 Views
Preview:
TRANSCRIPT
-
7/28/2019 Voip Ppt Final 1
1/21
VoIP
PRESENTED BY
Ankit Aggarwal
M.Tech 3rd Sem
(Digital Comm.)
-
7/28/2019 Voip Ppt Final 1
2/21
An Introduction to Telephone
The first telephone was invented in 1876 by Alexander
Graham Bell.
The first phone company was started in 1879
( International Bell Telephone Company (IBTC) and nowknown as American Telephone & Telegraph Company
AT&T).Slogan A phone in every household.
The device which allows conversation to two or moreusers when they are not in the same vicinity of each
other to be heard directly.
Earlier telephones were based on analog communication.
-
7/28/2019 Voip Ppt Final 1
3/21
VoIP
A recent application of Internet technology
Voice over IP (VoIP) which meansTransmission of voice over Internet
Introduction of VoIP in 1995 by Vocaltec Inc.
The use of the Internet that was originallydesigned to carry computer data to carry
voice
Voice over Internet Protocol Also known as :
Next Generation Voice Network
IP Telephony
Voice over Internet
Voice over Internet Protocol
Voice over Packet
-
7/28/2019 Voip Ppt Final 1
4/21
Why we need VoIP? Low cost.
Not only voice but also video is transmitted usingsimilar concepts.
Spreads at a fast pace
Independent
No geographical restriction
-
7/28/2019 Voip Ppt Final 1
5/21
A Basic IP Telephone System
The simplest IP telephone system uses two basic components:
-IP telephone: end device allowing humans to place and receive calls.-Media Gateway Controller: providing overall control and coordinationbetween IP phones; allowing a caller to locate a callee
-
7/28/2019 Voip Ppt Final 1
6/21
Interconnection IP telephone system needs to interoperate with PSTN or
another IP telephone system.
Two additional components needed for suchinterconnection: Media Gateway
Signaling Gateway
Media Gateway - translates audio between IP network and PSTN.
Signaling Gateway - translates signaling operations.
-
7/28/2019 Voip Ppt Final 1
7/21
How VoIP works?
Converting the voice signalADC (analog to digital)
DAC (digital to analog)
Voice (source) - - ADC - - - Internet - - - DAC - - Voice (dest)
Transmission of voice traffic in packets
-
7/28/2019 Voip Ppt Final 1
8/21
VoIP Components
Encoder
Packetizer
Playback Buffer
Decoder
Encoder Packetizer
Sender Receiver
NetworkPlayback
Buffer
Depacketizer Decoder
-
7/28/2019 Voip Ppt Final 1
9/21
Programmable buttons
Foot stand adjuster
Display button
Message button
Directories button
Help button
Settings button
Services button
Volume button
VoIP Phone
Speaker button
Mute button
Headset button
Navigation button
Keypad
Softkey buttons
Handset light strip
Touchscreen
11
12
10
13
15
16
14
17
9
8
7
1
2
3
6
5
4
-
7/28/2019 Voip Ppt Final 1
10/21
Advantages
Use computer and phone at same time
Do not need multiple phone lines
Unlimited talking time world wide
Local, long distance, international calls all the sameprice
Talk with several people at same time with noadditonal cost
-
7/28/2019 Voip Ppt Final 1
11/21
Disadvantages
Some VoIP services do not work during power outages
If a remote site fails connections may be unreachable
If there is congestion in the network it may cause delays, and increasedpacket loss
-
7/28/2019 Voip Ppt Final 1
12/21
Various Issues in designing
network The most important factors in the designing of the
network is
Service It is essential for maintaining customersatisfaction.
Cost A factor which is always involve in maintaining
profitability.
-
7/28/2019 Voip Ppt Final 1
13/21
What is Traffic
Traffic is defined as either the amount of data or
the number of messages over a circuit during a
given period of time.
It is also defined as the relationship between the
call attempts and the speed with which the calls
are completed.
-
7/28/2019 Voip Ppt Final 1
14/21
The most important factors that should be taken into the
account when analyzing the traffic -
Traffic Load measurement
Grade of Service
Traffic Types
Sampling Methods
-
7/28/2019 Voip Ppt Final 1
15/21
Factors in analysing the voip
traffic
There are following factors
Voice Codecs
Samples
Voice Activity Detection
RTP Header Compression
Call Arrival Patterns
-
7/28/2019 Voip Ppt Final 1
16/21
Various Issues in Analyzing VoiP
Traffic Delay Jitter - The delay experienced in receiving a
packet when a packet is expected to arrive at the endpoint at a certain time
Latency - The time taken for a packet to arrive at itsdestination
Bandwidth It is to be shared between voice andcomputer data
Packet loss - It is not acceptable
Reliability
Scalability Ability to add more telephone instruments
Security As it uses internet therefore it is vulnerableto the security risks.
-
7/28/2019 Voip Ppt Final 1
17/21
-
7/28/2019 Voip Ppt Final 1
18/21
-
7/28/2019 Voip Ppt Final 1
19/21
Analyzing VoiP by Vbuzzer
A type of soft phone system by which we can analyze the
VoiP system.
It is an internet telephony software which is not designed
to simply duplicate the traditional telephone system.
Users can send and receive voice calls to or from otherVbuzzer users on the internet.
-
7/28/2019 Voip Ppt Final 1
20/21
PC PCNetwork
Vbuzzer Vbuzzer
Vbuzzer test bed setup
-
7/28/2019 Voip Ppt Final 1
21/21
Call Setup Process in Vbuzzer
Vbuzzer
Caller
Proxy
Server
Vbuzz
erCallee
Invite Invite
100 Trying
180 Ringing
200 OK
ACK
200 OK
180 Ringing
100 Trying
top related