User Guide

14 Chapter 1. Advanced Topics
Point-To-Point Protocol (PPP)
PPP is an industry standard WAN protocol for transporting multi-protocol datagrams over point-to-point
connections. PPP defines a set of protocols, such as security and network protocols, that can be negotiated over
the connection. PPP includes the following protocols:
• Link Control Protocol (LCP) to negotiate PPP; i.e., establish, configure and test the datalink connection.
• Network Control Protocols (NCPs), such as:
TCP/IP routing Internet Protocol Control Protocol (IPCP)
IPX routing Control Protocol (IPXCP)
Bridge Control Protocol (BNCP)
• Security Protocols including PAP and CHAP
A more detailed description of the router’s implementation of some of these protocols appears the following
section. A list of PPP protocol conformance is included later in this section.
PAP/CHAP Security Authentication
Password Authentication Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP) under PPP
are supported by the router. However, security authentication may or may not be needed depending on the
requirements of the remote end.
The nature of the connection in a DSL environment (traffic occurs on a dedicated line/virtual circuit) does not
require authentication unless that is specifically required by the remote end, the ISP, or the NSP. When
authentication is not required, security can be disabled with the command
remote disauthen
.
IP/IPX Routing On Bridging to/from Remote Router On
Data packets carried IP/IPX routed; all other packets bridged.
Operational
characteristics
IP/IPX routing and allows other protocols, such as NetBEUI (that can’t
be routed), to be bridged.
Typical usage When only IP/IPX traffic is to be routed but some non-routed protocol is
required. Used for client/server configurations.
IP/IPX Routing Off Bridging to/from Remote Router On
Data packets carried All packets bridged.
Operational
characteristics
Allows protocols, such as NetBEUI (that can’t be routed) to be bridged.
Typical usage Peer-to-peer bridging and when the remote end supports only bridging.