“Extension” - is the extension of the telephone line (PBX) or the Centrex system. It works as an association and allows calling to certain telephone sets without the necessity of dialing the telephone number, but only by dialing a short combination of digits, reaching the desired subscriber.
MobiGater is a device which transfers your Skype calls to your mobile phone without the use of SkypeOut credits. It connects to your cell phone via a SIM card placed inside it, and using a USB cable to your PC and Skype.