Bay Networks 6300 Supplement Manual page 140

Chapter 6 Point-to-Point Protocol (PPP)
Remote Annex 6300 Supplement to the Remote Annex Administrator's Guide for UNIX
A-112
Negotiating the IP Address
The RA 6300 and the peer negotiate the IP address to be used on both
sides of the link. Any address sent as zero requests that the peer set the
address. Four parameters control the RA 6300 IP address negotiation:
address_origin, local_address, remote_address, and enable_security.
If address_origin is set to acp, the RA 6300 makes an ACP
dialup_address() call for the addresses to be used from the acp_dialup
file.
If address_origin is set to dhcp, or if it is set to acp and the remote
address field of the acp_dialup file is set to dhcp, the RA 6300 receives
a dynamically assigned IP address.
If address_origin is set to local (its default value), or DHCP and ACP
are not available, the RA 6300 defaults to using the local_address and
remote_address as the addresses. The RA 6300 allows the other side of
the link to select addresses only if these addresses are zero.
The RA 6300 uses two methods to negotiate the IP addresses. The
preferred technique is to use the NCP type 3 IP-Address option. If the
peer rejects this style of address negotiation, the RA 6300 falls back to
using the deprecated NCP type 1 IP-Addresses option.
In either case, the RA 6300 requires the peer to use both the local and
remote address of the RA 6300. To allow the peer to select addresses, the
RA 6300 addresses must be set to zero.
If each end has a zero address and the peer cannot provide both, or the
RA 6300 has a non-negotiable address, the RA 6300 and the peer will
never agree upon an address, and the link will fail to come up.
Book A