Enterasys Networks Security Router X-PeditionTM - Manual (Page 191)

XSR User’s Guide 8-1
8
Configuring PPP
Overview
The Point-to-Point Protocol (PPP), referenced in RFC-1616, is a standard method for transporting
multi-protocol datagrams over point-to-point links. PPP defines procedures to assign and manage
network addresses, asynchronous and synchronous encapsulation, link configuration, link quality
testing, network protocol multiplexing, error detection, and option negotiation for network-layer
address and data-compression negotiation. PPP provides all these functions through its three
main components:
• An extensible Link Control Protocol (LCP) for establishing, configuring, and testing the data-
link connection.
• A method for encapsulating multi-protocol datagrams.
• A family of Network Control Protocols (NCPs) for establishing and configuring different
network-layer protocols.
When negotiation is complete, PPP becomes the pipe that carries the network layer protocol data
units (PDUs) in the information field of the PPP packet. PPP offers high performance and error-
free transmission of user traffic from sender to receiver over a link.
PPP Features
The XSR PPP software module offers the following features:
• IP datagram encapsulation over a data link connection
• Synchronous and asynchronous communication modes
• Multilink Protocol (MLPPP) as defined by RFC-1990
• Multi-Class MLPPP, as defined by RFC-2686. This option is present in the PPP LCP
negotiation when enabled providing:
– Multilink Maximum Received Reconstructed Unit (MRRU)
– Multilink Short Sequence Number Header Format
– Endpoint Discriminator
– Maximum fragment delay
– Fragment interleaving, reassembly, and transmission sequencing
– Multi-Class option negotiation
• IPCP Network Control Protocol (NCP)
• Authentication of peer entities through:
– Password Authentication Protocol (PAP)