What is SIP?

Session Initiation Protocol or SIP is an Internet Protocol used to initiate or terminate live communication sessions. These may include anything from instant messages to phone and video calls to interactive multimedia conferences. Chances are that you will see many more implementations of SIP in the near future. In fact, over the last couple of years major players in the voice over IP industry have adopted SIP as their signaling protocol of choice.

 

What is a SIP address?

A SIP address is a lot like an email address in that it also serves as a locater of the user. SIP addresses even look very similar to email addresses. Like email addresses, they are comprised of two parts: a username, and a domain. For example, if your name was Mike, you might have the following identical SIP and email addresses:

[email protected]

SIP communication would be routed to Mike at his SIP address sip:[email protected] as email would be sent to Mike at his Email address mailto:[email protected].

 

Where do I get a SIP address?

The easiest way to get a SIP address is by creating an account with an online service. Like creating an email account with Google or Yahoo, you will be provided with an address (i.e. [email protected] or [email protected]). However, your SIP service provider may allow you to create SIP addresses within your own domain as well (i.e. [email protected]). SIP service providers like OnSIP allow customers to use the registered domain name of their companies to create SIP addresses free of charge.

Alternatively, you can also set up your own SIP server to host your SIP addresses.

 

How do people using old telephone systems call me on my SIP address?

For people using old telephones to reach you on your SIP address, you need to have a regular telephone number which forwards to your address. If you want to call people who are using regular telephones, your SIP service needs the ability to call out to regular telephone numbers. Usually, your SIP service provider can provide you with one or both of these services.

 

What can I do with my SIP address?

Your SIP address allows you to participate in SIP based communication over the Internet. As already stated, SIP can be used to initiate a variety of communication formats ranging from a phone call to collaborative conferences over existing Internet connections without the need of traditional telephone services.

What makes SIP even more powerful is that it is personal like an email address. While a telephone number is registered to a specific device, a SIP address follows the person it belongs to. This gives SIP users access to new features that standard landline telephone services simply do not offer. For example, SIP users can use a “find me, follow me” service so that they always get their important calls, regardless of whether they’re at home, at work, or at the beach. With the increasing prevalence of Internet telephony in the corporate and consumer markets comes the gradual migration from the use of telephone numbers to the use of SIP addresses.

 

From:http://www.onsip.com/about-voip/general-info/what-is-my-sip-address