Voice over Internet Protocol (VoIP) :-
Internet is widely prevalent and the cheapest medium of communication. Its development was originally for data transmission through Packet Switching such as Email, Internet Surfing & Downloading / uploading subjective information. However it has become now a methodology with a combination of group of technologies for the delivery of voice communications and voice-related multimedia sessions over Internet Protocol (IP) networks also known as IP telephony or Internet telephony.

The term Internet telephony specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than conventional public switched telephone network (PSTN).

VoIP is available onvarious smartphones, personal computers, and on Internet access devices. Calls and SMS text messages may be sent over 3G or Wi-Fi.
RST Infocom provides various services on VOIP including OBD, IBD, Missed Call Services, Call Centre Customisation etc.