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Point-to-point protocol

(also PPP)

Point-to-point protocol definition

Point-to-point protocol is a data link layer protocol used to establish a direct connection between two nodes in a network. It is commonly used to connect a computer to the internet through a telephone line or a DSL modem. Point-to-point protocol provides a standard method for transporting multi-protocol data packets over point-to-point links.

PPP is a successor to the serial line internet protocol and has several advantages over it, like error detection and correction, automatic negotiation of connection parameters, and supporting multiple network protocols.

See also: node

How does the point-to-point protocol work?

  • Connection. The PPP session starts with a physical layer connection, like dial-up or DSL. The PPP protocol is then initialized on both ends of the connection.
  • Establishing a link. The link control protocol is used to establish and configure the PPP link between the two nodes. It negotiates link parameters, detects link quality, and authenticates the connection.
  • Authentication. PPP supports various authentication methods to ensure secure communication between the two nodes. The authentication process is typically initiated by the ISP server, which requests the user's credentials.
  • Data transfer. With the PPP link established and the network protocol negotiated, data can be transferred between the two nodes.
  • Termination. The PPP session is terminated when either the user or the ISP server disconnects. The PPP protocol releases all resources used by the session and resets the link.