VoIP Cookbook: Interconnectivity and Telephone Number Allocation
Questions mostly asked by VoIP users is whether VoIP can be used to dial—and receive calls from—a PSTN or cellular number, since one of our purposes in using internet telephony is that we want to have this two-way interconnectivity, particularly to be able to receive calls from PSTN or cellular. Unfortunately, this might not be as easy as we think, as calls originating from PSTN or cellular can reach often only telephone numbers legitimately recognized by the PSTN or cellular. These numbers are allocated by E.164, the official numbering system acknowledged by the International Telecommunication Union.
However, the good news is that there are some leeways making it possible for us to call PSTN or cellular numbers using VoIP. One of which is by subscribing to a VoIP provider that provides us with PSTN numbers. On the other hand, we can also register our PSTN number to international VoIP network so our VoIP account can be recognized as a legitimate PSTN number. This section will help you understand in detail the technique for obtaining the number. We could get a free phone number from Washington State, US, (http://www.ipkall.com) which enable cellular/PSTN users to call us on VoIP network.
Note that to receive a call from PSTN provider, it is sufficient to use a computer, softphone and internet connectivity, preferably kept online for 24 hours, as if we are using ordinary phone. Obviously, as we have explained earlier, it is preferable to use VoIP hardware such as IP Phone.
 More Detailed
- VoIP Cookbook: Getting Free Washington State Telephone Number
- VoIP Cookbook: Free Internet Country: Country Code +882
- VoIP Cookbook: Introducing your country code to International VoIP network
- VoIP Cookbook: VoIP Rakyat's ENUM
- VoIP Cookbook: Connecting to PSTN and Cellular Using VoIP Discount
- VoIP Cookbook: VoIP Cheap