Voip monika

VoIPMonika lagwal0151MCS013

MITS

Contents•What is VoIP?• How does it work?•VoIP Architecture •Who uses VoIP?•VoIP Network Model•Components•Advantages and Disadvantages of VoIP•Security Risks

What is VoIP?•The Voice over

Internet Protocol enables you to use your IP network to make phone calls.

•However, it is not just used for phone calls, it is used for general voice communications over the internet.

VoIP – How does it work? •Converting the voice signal

▫ADC (analog to digital)▫DAC (digital to analog)

Voice (source) - - ADC - - - Internet - - - DAC - - Voice (dest)

•Transmission of voice traffic in packets

VoIP – How does it work? (2)•1. Compression – voice is compressed

typically with one of the following codecs, G7.11 64k, G7.29AB 8k, G723.1 6.3k

•2. Encapsulation – the digitized voice is wrapped in an IP packet

•3. Routing – the voice packet is routed thru the network to its final destination

IP Network

Multimedia PC

Multimedia PC

Initially, PC to PC voice calls over the

Internet

VoIP Architecture

PSTN(DC)

Gateway

PSTN(NY)

Gateway

Public Switched Telephone Network

Gateways allow PCs to also reach phones

…or phones to reach phones

Who uses VoIP?• VoIP is beginning to be used in a lot of

business. This is because it is cheap.• Microsoft is using VoIP for their ‘Xbox’ live

service. Enabling customers to be able to talk through a headset to each other. However, they do charge a small fee for the service.

• Xbox Live is an online multiplayer gaming and digital media delivery service created and operated by Microsoft.

• Party Chat will return on Xbox Live for Xbox One, and may increase its limit of 8 people chatting simultaneously. The quality of the party chat on the Xbox One is said to be much clearer than its precursor, the Xbox 360, as it will utilize Skype.

VoIP Network Model

SIP:Session Initiation Protocol (SIP), an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls, multimedia distribution, and multimedia conferences.RTCP :carries statistical and control data.RTP :Real-time Transport Protocol  is a network protocol for delivering audio and video over IP networks RTSP :Real Time Streaming Protocol .The protocol is used for establishing and controlling media sessions between end points.

Components •VoIP Protocols•VoIP Gateway•VoIP Codecs

VoIP Gateway•A VoIP gateway is a gateway device that

uses Internet Protocols to transmit and receive voice communications (VoIP).

VoIP Codecs•Codecs are used to convert an analog

voice signal to digitally encoded version. Codecs vary in the sound quality, the bandwidth required, the computational requirements, etc.

Advantages of VoIP1.Low Cost .

2. No extra cables, no extra cost .

3. Call screening.

4. With VOIP PC-to-PC, calls are free no matter the distance and PC-to-Phone charges are nominal.

5. You may call or message or do both at the same time with VOIP services.6. You may access your VOIP account just like your email Id from any where

in the world as long as you have an internet phone. This makes it easy for those who travel frequently to make calls frequently to those back at home at local call rates, no matter where they are.

Disadvantages of VoIP• Some VoIP services do not work during power outages or when the

internet connection is down.  It is a good idea to install a backup power supply or have a mobile phone as a backup.

•  Call quality is affected by the quality of broadband connection and the performance of your PC.  So make sure you have good internet connection and both your computer hardware and software are running properly.

• Latency and traffic. With VOIP emergency calls, it is hard to locate you and send

help in time. Some times during calls, there may be periods of silence

when data is lost while it is being unscrambled.  No standard protocol is applicable.

Security Risks IN VOIP•As VoIP uses the Internet, for example, it

is vulnerable to the same type as security risks▫Hacking▫Denial of service▫Eavesdropping

THANKYOU