voip power point presentation
TRANSCRIPT
-
8/9/2019 VOIP Power Point Presentation
1/23
1
VOIPVOIP(Voice Over Internet Protocol)(Voice Over Internet Protocol)
By:-Nikhil Garg
ECE-030
New age digital technology for convergence of voice ,video and data
-
8/9/2019 VOIP Power Point Presentation
2/23
2
INTRODUCTIONINTRODUCTION
Voip is one of the fastest growing
Technology
The basic concept behind this technology isthe transportation of real time voice over
network such as internet
-
8/9/2019 VOIP Power Point Presentation
3/23
3
Why VOIPWhy VOIP
A major implementation of VoIP is to bypasslong distance calls by transporting calls over
an IP network
VoIP allows communications on existing IPnetworks without adding additional lines or
bandwidth
Wireless handsets can roam and still beconnected to the main office via IP
-
8/9/2019 VOIP Power Point Presentation
4/23
4
Communication TechniqueCommunication Technique
There are two Techniques for commuter &
Telecommunication network.
Circuit Switching:- Whenever a call place onnetwork, System seek out a physical path
between your phone and destination phone,
communication takes place after an end to end
connection is established. It will continue untilthe call is finished
-
8/9/2019 VOIP Power Point Presentation
5/23
5
Communication TechniqueCommunication Technique
Packet Switching:- In this technique
whole data can be divided into packets
with full information. These packetstransmitted by the network. So it not
require any fixed path.
-
8/9/2019 VOIP Power Point Presentation
6/23
6
ITEM CIRCUIT
SWITCHED
PACKET
SWITCHED
Dedicated path Yes No
Bandwidth available Fixed Dynamic
Store and Forward
Transmission
Not Possible Possible
Each packet follows the
same packet route
Yes No
Call setup Required Not Required
Comparison OfCircuit Switched and Packet
Switched
-
8/9/2019 VOIP Power Point Presentation
7/23
7
Components of a VoIPComponents of a VoIP
SystemSystem Gateway :-Gateways perform the following function
1. Search Function :- Conversion of phone no into IPaddress
2. Connection Function :- Connection Between
originating gateway to destination gateway
3. Digitizing Function :- Convert into digital form
4. Demodulation Function:- Re-conversion
5. Compression Function:- Used for compression
-
8/9/2019 VOIP Power Point Presentation
8/23
8
GatekeeperGatekeeper A Gatekeeper is device that knowA Gatekeeper is device that knowhow many users are connected and where they arehow many users are connected and where they are
located.located.
IP TelephonesIP Telephonesprovide enhanced service
suited to VoIP.
PC Software Phone:- Used forPC
(Microphone & Software that permits voice
over internet)
-
8/9/2019 VOIP Power Point Presentation
9/23
9
How it works ?How it works ?
Analog voice is received by a CODEC (coder / de-
coder)
Complex circuitry then samples the voice and
compares the voice to a codebook. This codebook is
used by both the coders and decoders.
Once sampled and matched with the codebook thevoice is now presented as data
Some codebooks are of different sizes and have a
different fidelity
-
8/9/2019 VOIP Power Point Presentation
10/23
10
These codebooks are recommended standards that
copies voice samples into different sizes
Once voice is sampled and replaced by code thevoice can then be formed into data and transported.
The usual transport method uses the IP (Internet
Protocol) standard.
IP uses many layers associated with the OSI model
to form, control, administer, and transport data.
-
8/9/2019 VOIP Power Point Presentation
11/23
11
Voice to IP
Network
Compress
Create Packet
Add Headers
CODEC
Voice
-
8/9/2019 VOIP Power Point Presentation
12/23
12
IP to Voice
CODEC
Process Header
Decompress
Network
Voice
-
8/9/2019 VOIP Power Point Presentation
13/23
13
AdvantagesAdvantages
Integration of voice & data:- Large Enterprises shifttheir business from private network to public network to
achieve better economics of scale, still they require voice on
network .
Simplification :- It support all form of communicationover one network rather than to build up separate network.
Network Efficiency :- Integration of voice of dataeffectively fills up the data communication channels, so it
provide bandwidth consolidation.
-
8/9/2019 VOIP Power Point Presentation
14/23
14
Cost Reduction :- It is cheaper to make an IPtelephony call, then to make a call by PSTN
Engineering Economics:- It is economical touse IP telephony which takes up 6-8 Kbps for one
call while PSTN call takes 64 Kbps.
-
8/9/2019 VOIP Power Point Presentation
15/23
15
Application & Services Of VoIPApplication & Services Of VoIP
Sound Grading :- PSTN supports one grade i.e. 4KHz while VoIP can supports higher grade.
Web Call Center :- More information about product (e-commerce).
Video Telephony
Remote Telephony:- By this service remote userscan use the resource available to the network.
-
8/9/2019 VOIP Power Point Presentation
16/23
16
Teleconferencing :Teleconferencing :-- User can share documentsthrough electronic means, Files can be transmitted.
IntegratedIntegrated Messaging :-User can get all themessage at one location from where he can access
them according to his convenience (Unified
Messaging).
-
8/9/2019 VOIP Power Point Presentation
17/23
17
ArchitectureArchitecture
There are two different architecture.There are two different architecture.
PC to PC :- A user places a call by specifying the IP
address of the recipients. All sampling ,compressionand packetization of the voice signal occurs in sender
PC, While play out of the receiving signal occurs
through a sound card on the receiverPC.
-
8/9/2019 VOIP Power Point Presentation
18/23
18
Gateway To Gateway (Phone to Phone) :Gateway To Gateway (Phone to Phone) :--
First user call an gateway that is near to centerFirst user call an gateway that is near to centeroffice, user identified and asked to enter phone no.office, user identified and asked to enter phone no.of the intended recipents.Then sender gatewayof the intended recipents.Then sender gatewaythan looks up and initiate session with the IPthan looks up and initiate session with the IP
address of gateway that is close as possible to theaddress of gateway that is close as possible to therecipient.An end to end communication canrecipient.An end to end communication canproceed with voice sent in IP packet between twoproceed with voice sent in IP packet between twogateway. Encoding and packetization occur in thegateway. Encoding and packetization occur in thesender gateway. Central office digitize the voicesender gateway. Central office digitize the voicebefore passing it to gateway.before passing it to gateway.
-
8/9/2019 VOIP Power Point Presentation
19/23
19
Packet LossPacket Loss
In IP network, IP packets from many sources are
queued for transmission over an outgoing link in a
router, packets are transmitted one by one from
the head queue.A
n arriving packet is lost if thereis no space in the queue, router become congested
resulting in a Packet Loss. Packet Loss can cause
severe damage to voice quality forIP technology.
Each IP packet contain 40 to 80 ms of speechinformation.
-
8/9/2019 VOIP Power Point Presentation
20/23
20
A
no. of technique used to solve packet lossproblem.
Network Up gradation :- Upgrade IP network
infrastructure
Silence Substitution:-Silence substitute in place ofpacket loss.
Packet Repetition :- Replaying the last correctly
received packet in place of the lost one
Packet Interpolation
-
8/9/2019 VOIP Power Point Presentation
21/23
21
Packet DelayPacket Delay
Timing is an important characteristic of voice, twosyllables of a word are uttered with an interval.This time should be as small as possible. Toomuch delay can impair voice in several ways.
Following is a discussion of a various sources ofdelay in VoIP.
Codec Delay :- The primary function of thiscodec is to a conversion, compression to reduce
the bandwidth requirement. This will introducedelay in codec.
-
8/9/2019 VOIP Power Point Presentation
22/23
22
Serialization Delay :- The time to take to place a
packet on the transmission line, higher line speeds, it can be greatly reduced
Queuing Delay:-Queuing delay occurs at various
switching and transmission point of the network
such as router & gateway (Waiting Time). Network Jitter :- Variance in the inter frame
arrival time at the receiver is called jitter and is
potentially more disruptive for VoIP than delays.
-
8/9/2019 VOIP Power Point Presentation
23/23
23
THANK YOU!THANK YOU!