SIP (Session Initiation Protocol) is used by many people around the world to communicate over IP network using their computers and mobile devices.
What is required:
- A SIP account – this can be obtained from many providers, one of them – Sipmobile.
- A SIP client – there are many SIP client, developed for different computers, operating systems and mobile devices. You can choose both free and payed. Also you can use hardware SIP phones from different vendors.
- Internet connection with sufficient bandwidth and quality for voice and video (if you use video). Most home and office networks are quite good for SIP. For mobile devices you can WiFi connections or modern 3G, LTE networks. With proper settings there are many chances to obtain good quality of audio and video.