Session Initiation Protocol (SIP) is a protocol that initiates and manages interactive user sessions involving voice, video, instant messaging, and other such multimedia sessions. It is a 3GPP (Third Generation Partnership Project) signaling protocol. It is one of the major signaling protocols used in Voice over IP (VoIP).
SIP was developed by IETF MMUSIC Working Group in an initiative to create a more robust standard compared to the H.323, which is a current widely used standard for voice sessions. The need was to cater to the increasing demand put by services such as video conferencing, unified messaging, and voice chatting, which are now being implemented through Internet.
SIP is based on Hypertext Transfer Protocol (HTTP). It basically deals with embedding call setup and signaling features in networking elements such as user agents and proxy servers. The signaling and call setup can be used by IP-based communication system to support the call processing functions and features present in the Public Switched Telephone Network (PSTN). SIP enables a VoIP application to have the same kind of high quality and reliability that traditional telephone systems can deliver. SIP adds quality and reliability to VoIP, which until recently has been associated with the term low cost alternative.
SIP handles the signaling part of a communication session. It serves as a carrier for the Session Description Protocol (SDP). SDP handles the media portion of the session. The transmission of voice and video content are done by the Real-time Transport Protocol (RTP). A SIP session thus involves packet streams of RTP. SIP is a part of the protocols involved in a multimedia session.
The major advantage of SIP is in its support for both IP and conventional telephone communication. Communication service providers can leverage on this protocol to interconnect conventional telephone and IP communication services. This especially sounds good for the vendors of VoIP telephony, wherein both the domains are involved. Owing to SIPs roots in HTTP, voice based application can also be seamlessly integrated with web services.
SIP is scalable, easy to implement, and requires less setup time than its predecessor protocols. Being text based, it is easy to program. It is a peer-to-peer protocol, requiring no implementation in the network level. The logic is implemented at the communication endpoints, which may be in hardware or software level. Real time sessions are established when and where required. Since SIP can be used to modify any session in progress, a normal telephone call session can be converted into a multi-party videoconference. Users can join in the session no matter what kind of terminal he is using or where he is located. The other person may be logged on to Internet through a PC, or may be traveling with a cell phone.
SIP holds lot of promise in today and tomorrows communication world. It has been established as a standard for call control and signaling on 3G cell phone networks by the Third Generation Partnership Project (3GPP). This means that all multimedia and IP voice call signaling will be done through SIP. New services involving fixed network IP services can thus introduced with ease.
John K represents AccessDirect, a leading provider of PBX phone systems (hosted/virtual).
This article has been published by John K, who represents AccessDirect, a leading service provider of PBX phone systems (hosted/virtual). For more information visit the company at http://www.messagingservice.com.
Author: John Kinskey
Article Source: EzineArticles.com
Provided by: Canada duty
Related Posts -
Minimize Your Phone Bill with VoIP Broadband phones are here for quite some time and is definitely the future of telecommunications. These phones are used to make telephone calls via PC over internet thus drastically cutting down the cost of your huge telephone bills. In UK and US, broadband and internet phones have become a household...... - VoIP Business Phone Service - Which Solution is Right For Your Business? One of the biggest expenses for any business, after staff costs, is the telephone bill. Businesses who have staff working away for the company offices or even abroad, are finding that the need to stay in contact is costing them more and more as telephone prices rise. There is......
- Office Phone Systems With PBX Technology Office phone systems with PBX technology help in the smooth running of any business establishment. These services are mostly used by small and medium sized businesses because these are less expensive than the conventional premise based communication systems. A PBX service can be obtained from a hosted PBX service......
- Call Forwarding and Call Transferring - Follows You The Voice over Internet protocol or VoIP has made the long distance and international calling at significantly lower rates. Besides its cost saving feature, new VoIP technology has enabled IP PBX system to offer easy integration with existing system. The IP PBX system is characterised with low operating cost.......
- Free IP Telephony Free IP telephone services are available to make national and international phone calls by using a computer and a mouse. To get these free services, you need a computer with an Internet connection using WiFi, broadband or a dial-up network supported by T-I, DSL, Fiber, Wireless, ATM, Cable or Frame......
Related Websites -
Getting Out of Debt Quickly pt 1 You are probably familiar with this feeling: Your bills are constantly piling up, but you feel so far behind that you simply cannot bear to even open them. When you do open them, you quickly realize that there is only enough saved up in your bank accounts for you to...... - Before Railing Apple or AT&T, Do You Know What Google Voice Does? I had to laugh while browsing through comments on one of the articles on Digg about how the Google Voice App for the iPhone was rejected. While I would totally agree with the consensus that Apple is treating its developers poorly and walking on thin ice with them (I said......
- Ways to Save Money on Your Phone Bill According to the CITA or the Cellular Telephone and Internet Association, there are over 100 companies providing different forms of phone service all across the country. This means you are using one of them at home and in a recession, you have to figure out different ways to save money......
- Does taking it to the top do any good? A colleague at work has recently taken it upon himself to be proactive in voicing his dissatisfaction about customer service to the store manager. By most accounts, he appears to be a tough customer to please. He likes answers to his questions right away, he likes problems to be fixed......
- Web’s Doomsday Is Round The Corner The digital doomsday is round the corner. In exactly 1,272 days there will be web chaos in the world as we run out of Internet addresses. More than 85 per cent of the available addresses have already been allocated and the rest will run out by 2011, according to a......
Related posts:
[...] news by Alliant DataTel, Inc. « Your Windows 7 upgrade checklist: what you can do BEFORE starting the upgrade How [...]