Q.Which of the following options is the correct protocol used for phone calls over the Internet? (A) PPP (B) FTP (C) HTTP (D) VoIP

Phone calls over the Internet leverage a technology that converts analog voice signals into digital packets, which are then transmitted across an IP network, such as the Internet. This method allows for voice communication without relying on traditional circuit-switched telephone lines. …

The question asks about the protocol used for making phone calls over the Internet. To understand this, we first need to grasp the fundamental idea behind transmitting voice digitally across a network designed for data. This concept is known as Voice over Internet Protocol, or VoIP.

Traditionally, phone calls relied on circuit-switched networks, where a dedicated connection was established between two phones for the duration of the call. VoIP, however, leverages the packet-switched nature of the Internet. It works by taking analog audio signals (your voice), converting them into digital data packets, and then sending these packets over the Internet. Once these packets reach their destination, they are reassembled and converted back into an audible voice signal. This method allows voice communication to be treated just like any other data traffic on the Internet, offering significant advantages in terms of cost and flexibility.

Now, let's look at the given options:

• VoIP (Voice over Internet Protocol): As discussed, this is the technology and the overarching protocol suite that enables voice communication over the Internet. It encompasses various specific protocols like SIP (Session Initiation Protocol) for setting up and tearing down calls, and RTP (Real-time Transport Protocol) for carrying the actual voice data. In the context of a multiple-choice question asking for the protocol, VoIP is the most appropriate and direct answer, representing the entire system for internet telephony.

• PPP (Point-to-Point Protocol): This protocol is primarily used to establish a direct connection between two networking nodes. Historically, it was widely used for dial-up Internet access, allowing a computer to connect to an Internet Service Provider (ISP) over a telephone line. While it facilitates an Internet connection, it is not the protocol for carrying voice calls over that Internet connection. Its role is at a lower layer, establishing the link itself. …