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PPP Link Configuration Overview
A PPP (Point to Point Protocol) connection between two routers may
use a number of Network Control Protocols (NCP) for
communication. An IP router connection will use the Internet
Protocol Control Protocol (IPCP) NCP for all IP communications. An
IPX router connection will use the Internet Packet Exchange Control
Protocol (IPXCP) NCP for all IPX communications.
In order to establish an IPCP or IPXCP link connection between two
PPP routers, either a numbered link or an unnumbered link connection
must be established. The two types of link connections are available to
allow for greater flexibility between vendors products.

Numbered Links

A numbered link assigns a network address (either IP or IPX) to both
ends of the WAN connection. In a numbered link configuration, the
WAN connection may be viewed as another LAN network with the
two PPP routers simply routing information between their local LANs
and the common connected WAN network.
Because the WAN is considered to be a separate network, each of the
stations on that network must be assigned a network address. If a
numbered IP link is to be established, then each WAN interface must
be assigned an IP address on a unique IP network. The WAN IP
network address must be different than the two existing networks that
are being connected together with the PPP routers.
If a numbered IPX link is to be established, then each WAN interface must
be assigned an IPX node address on a unique IPX network number. The
WAN IPX network address must be different than the two existing
networks that are being connected together with the PPP routers.
The IP address of the local WAN link is defined as the Local IP Address
within the remote site profile settings. The IP address of the WAN link of
the remote PPP router is defined as the Peer IP Address within the
remote site profile settings. The WAN IP network number is defined by
defining a subnet size to use when defining the local IP address. The size
of the subnet will determine the IP network number used.
The IPX node address of the local WAN link is defined as the Local IPX
Node within the remote site profile settings. The IP address of the WAN
link of the remote PPP router is defined as the Peer IPX Node within the