What is a Virtual phone number?
A virtual phone number is a VoIP number or gsm subscriber phone number. It is similar to any other phone number, mobile or fixed-line subscribers have. But the main difference is that this number does not belong to any sim card or to any fixed line device.
VOIP providers allocate the number along with the VOIP account. A virtual phone number has many advantages. The main advantages are for business. For e.g a company having its customer care office in India, but the service is launched in may other countries. They have a local number for each country. It is a very difficult task to set up customer care offices in each country. Here comes the main role of the virtual number.
Services provider buys a virtual number for each country and the callers feel that they are talking to local guys. Virtual number provider routes all calls to the India call center.
VoIP and Virtual Number:
The VoIP enables the virtual number concept. A no VOIP number has either the sim card or a fixed-line. The VOIP gateway provider terminates the request for the virtual number and connects to the actual number for voice and data. So it’s like a getaway between IP and PSTN network. As all is on the IP network this enables a cost-effective service to the service user.
The voice Call flow for Virtual Number :
Voice is the primary service that a telecom network provides. When a user dials the virtual number. The call reaches the service provider. Provider Knows that this is called for the virtual phone number by looking at its database. If the phone number is not provisioned then the call is dropped, else the actual number is found and the provider initiates a new call towards the actual number and connects both the calls. On VoIP side the signaling protocol is SIP and on PSTN side the signaling protocol is ISUP. Sip if for setting a voice session over IP network and ISUP is the protocol for setting a Voice Channel over the PSTN network or SS7 network. The called actual number can be a mobile number, a fix line number or a call center number via SIP trunking.
SMS Flow for virtual number:
SMS or text is another basic service for any number. Similar to voice, the VOIP provider for virtual number forwards the SMS to the actual number and the sender gets the delivery report for the successful submission for the number.