SIP Phone System - What, How & Who?

A SIP phone system is simply a phone system that places calls over the internet rather than the traditional phone lines, the vast majority of VoIP phones today use the SIP protocol, making the terms often used synonymously. SIP phone systems have become incredibly feature rich and and far more flexible than traditional phone systems. Most SIP phone systems support unlimited phones/extensions, feature rich voicemail, conference calling, call forwarding, call queuing, interactive voice response and number of other calling features. Traditional phone systems rarely support all these features, and if they do, they cost in the thousands of dollars (at least) to get up and running.

SIP (Session Initiated Protocol) is simply the protocol that powers VoIP. It was developed by the IETF in 1996 and has since evolved to become incredibly flexible, reliable and capable of handling pretty much any call feature that any phone system has ever had to handle - this is likely because of it's huge adoption among small & medium size businesses, roughly 16% of SMB's have SIP phone systems as of 2014. The protocol is highly technical and meant to be interfaced only with phone system engineers & developers - certainly, not the end user of the phone system. See more about SIP as a protocol on wikipedia , or if your really dedicated, take a look at the SIP protocal specifications .

How to set up your own SIP phone System

If you are looking to set up your own SIP phone system, RingRoost's PBX builder offers a simple drag and drop interface that allows you to do this without any technical or system engineering experience. Using the PBX builder (a PBX is just a phone system), you can set up multiple phones, each with their own extension, voicemail, and a number of advanced call features.

Most SIP phone systems will not have a graphical user interface for setting them up, generally you need to install your own hardware / software and then program a number of setting in order to meet your business requirement. If you are looking to set up your own SIP phone system without using a graphical interface, here is a list of some great SIP software tools that you will almost certainly need.

• Asterisk

  Asterisk is a open source SIP signaling engine, it also has a number of other features required in most phone systems, including codec translations, and voicemail features. Asterisk does not have a graphical interface (out of the box), and is designed for telecommunication professionals or hobbyist, most average phone users should not expect to able to install and set up Asterisk. http://www.asterisk.org/

• SipSak

  SipSak is a Linux command line tool for sending simple SIP requests. It's a must for any professionals setting up a SIP phone system. http://sourceforge.net/projects/sipsak.berlios/

• Elastix

  Elastix is another SIP signaling and communication software suite, it's similar to Asterisk in it's functionality, but not as widely used. http://www.elastix.org/

• Zoiper

  Zoiper is probably the best softphone (phone on your computer) and runs on top of the SIP protocol. Anyone who is setting up SIP phone system should probably download and try out Zoiper (if for no other reason than to understand how SIP works). Zoiper can be, and is often used for businesses to place and receive calls. It's also a great testing tool for ensureing your network/ SIP provider is working, when setting up hard phones on your phone system. http://www.zoiper.com

• Linphone

  Linphone is another softphone, meaning a phone that runs on your computer. It's probably not the best for placing/receiving calls regularly, but is very good for testing SIP systems. http://www.linphone.org

SIP Phone Market & Growth

Phone system's using SIP make up a significant percentage of the SMB communication systems market, roughly 16% of the 75 million SMB's in 2014 use SIP phone systems. More shockingly is the growth rate of the SIP phone system market, the SIP/VoIP market on the whole is growing at rate of about 13% per year. Our internal research projections of the SIP market predicts that almost 40% of SMB's will be powered by SIP phones by 2023.

SIP vs Other Protocols

There are many other communication protocols in traditional phone lines, however comparing those protocols with SIP is not really fair as SIP goes over internet and the traditional phones go over PSTN.

There are a few other communication protocols that "compete" with SIP and go over the internet. The most notable protocol is a protocal call IAX , this protocal is generally used when communication betweet two servers rather than a server and client or SIP phone. Often times SIP/IAX can work together in a large phone system, however many systems will just use one or the other for the vast majority of communication signaling. Some other communication protocols have emerged that do a simliar thing as SIP, however they are almost always from a private organization and proprietary in nature, a notable example is the Skype Protocal.