What Is PPP?

Date First Published: 13th June 2022

Topic: Computer Networking

Subtopic: Internet Protocols

Article Type: Computer Terms & Definitions

Difficulty Level: 6/10

Learn more about what PPP is in this article.

Stands for Point-To-Point Protocol. PPP is a data link protocol used to directly transfer data between two nodes (points). PPP has been used by ISPs for dial-up connections as data packets cannot be sent over a modem line on their own without a data link protocol that is capable of identifying where the sent data frame starts and ends.

PPP can transfer data over TCP or UDP. It provides additional features, such as password protection, error correction, and encryption. Once the two nodes are connected, PPP is responsible for link control, data control, and protocol encapsulation. It was defined in RFC 1661 in 1994.

PPP can use different physical transmission mediums, such as simple serial cables, mobile phones and telephone lines. TCP and IP were introduced for the purposes of data communication and only have specifications for Ethernet networks, meaning that TCP and IP do not support point-to-point connections. PPP was introduced for point-to-point connections with Ethernet.

Process Of PPP

PPP is often viewed as a peer-to-peer protocol, meaning that both sides of the link can be used to make a PPP connection. However, a PPP server usually exists that works as a connection hub for several PPP clients. The PPP server remains inactive until a PPP client attempts to make a connection.

The server will respond to the client with an authentication request if the server is configured for authentication. Once authenticated, the Network Control Protocol is used, usually Internet Protocol Control Protocol between systems. Once the connection has successfully been established, the clients can begin exchanging data with each other.