Voice over Internet Protocol (VoIP) is a protocol for the transmission of voice via the Internet. In plain English, this gives one the ability to make voice calls via the Internet. This is also known as Internet Telephony, Broadband Phone, IP Telephony, or Voice Over Broadband.
The providers of Internet telephony use different protocols for transmitting voice signals over an IP network on the Internet; these protocols are referred to as Voice over IP.
The idea of being able to make telephone calls over the Internet has been around ever since the beginning of the development of the Internet. The Network Voice Protocol was an experiment carried out by the people who founded the ARPANET, which were the progenitors of the Internet as we know it today.
The results of these experiments were that the Internet was being used to transmit voice signals as early as 1973. However, this technology became available to end-users, like you and me, from the 1990s. The later part of the 1990s witnessed many technological developments in this field, which has resulted in VoIP facilities being commonly available today.
There are basically two types of VoIP services: Direct Inward Dialing (DID) services and Access Numbers facilities. DID services directly connect two VoIP users with each other, while Access Numbers facility requires a caller to input the extension number of the receiver.
There are many advantages of IP telephony which have contributed to their popularity. These include the various features which most service providers ardently advertise, such as 3-way-calling, call forwarding, automatic redial, and caller ID facilities.
The advantage here is that VoIP providers provide these services for free, while regular telecom companies usually charge for these services. Another advantage is that these calls can be transmitted on the same line as the broadband connection.
This allows the service providers to provide a telephone line along with a broadband connection, as an add-on. The broadband phone has, thus, become an integral part of several homes and offices.
The best advantage, however, is that VoIP calls are independent of the location of the callers. The only thing needed is an Internet connection from a VoIP service provider.
Often, this service can also be combined with different other services such as video conferencing, audio conferencing, data transfer, and so on, which are useful in several offices, and have become extremely invaluable to international businesses for their efficient functioning.
Hurdles to Overcome
Although the advantages are many, the technology still has many hurdles to overcome. Typically, voice calls over the Internet are often accompanied by a time lag―there is a lag between the time you speak and the caller hears your voice. Also, being routed over the Internet, these voice calls can be blocked by firewalls on other computers.
Data signals are usually transmitted as packets. Sometimes, there can be packet loss during transmission, which is quite problematic for users. Calls made over IP often cannot be connected to telephone users who use pulse dialing services. Also, the VoIP system needs to be connected to generators which will not interrupt the call during power failures.
However, many technological innovations and experiments are being carried out, even as we speak, to ensure that these hurdles are overcome. Thus, voice over Internet telephony has not just become a buzz word, but is a very important business tool for today's commercial organizations.