Numbered and Unnumbered Links
When routing and using the AccessBuilder 500’s FastConnect protocol over ISDN links as opposed to PPP, you have the option of using numbered or unnumbered links.
A numbered link requires a valid IP address to be configured for both ports connected to each end of the link. The IP address used must be for a different subnet or network than that used by either LAN at each end of the link. An example is shown in Figure
Figure A-6 Example Of A Numbered Link
By default the ISDN port has an IP address of 10.0.0.1. This is set to allow remote Telnet connections to the unit to enable configuration but must be changed when configuring the unit to allow correct operation. If you use the Quick Configuration (QC) option to configure the unit to operate over ISDN, the Port IP Address is set to unnumbered.
In most instances you should use unnumbered links. This is easier to configure and does not use network addresses which may be in short supply.
