A WiFi SIP phone uses session initiation protocol to communicate to other phones across the world. These revolutionary devices take advantage of the protocol to communicate quickly and easily. While similar to VoIP WiFi phones, they are not exactly the same. A WiFi SIP phone specifically uses the SIP to initiate communications.
How An WiFi SIP Phone Works
The phone will first off establish a connection to the local WiFi network. This requires that you have the right pass code to get through if it is a secured network. At home this is done very easily by simply entering the code that you have put onto your router. If you are on a network you do not have administrative rights to this can be a bit more of a problem. However, if it is a free network then you should have no problems getting in touch with the administrator and having them pass you a key to get on.
Once you have established connection with the network you can then begin sessions with other VoIP devices or make outbound calls. There usually is software installed on the phone that will facilitate this. There are many different kinds of software out there, but it is best to go with whatever is installed on the phone. This should make the WiFi SIP phone seem to operate just like any other normal phone and once you get the hang of it you will have a hard time telling the difference. Some people seem to experience a bit more lag on a WiFi SIP phone, but this is more a problem with the network then the actual phone.
There are many different kinds of WiFi SIP phones out there, but they all perform and have similar functions. One thing to remember though is that a WiFi SIP phone is not a replacement for a normal phone simply because they do not emergency response capabilities.
Without this a WiFi SIP phone will never be able to completely replace a cellular phone. They can be great to have at home though if you have a wireless network because there is no cost for making calls and no monthly bill other then your normal internet bill. You will need some kind of broadband connection to run the phone as while they do not require a ton of bandwidth, a simple dial up modem is not sufficient. Also, you would need to tie up the phone line to be able to get incoming calls.