Chapter 1: Understanding ISDN and the Express XL/XLT
20 Express XL/XLT User Manual 61200.070L1-1
be assigned under the Configuration/IP/NAT menu that allows incoming HT-
TP, FTP, and mail server requests from the Internet to be translated and for-
warded to this address on the user network.
Configuration
The Express XL/XLT is configured using a menu-based interface. This inter-
face can be accessed via the maintenance port using any asynchronous VT100
terminal or personal computer running a terminal emulation program, or via
the LAN using a Telnet client program. To use the Telnet interface, the Ex-
press XL/XLT must first have an IP address programmed into it via the main-
tenance port. The factory default is 10.0.0.1.
Security
Security on network devices is a major concern for almost anyone with a net-
work. The Express XL/XLT provides many tools for securing the local net-
work from hostile users. Incoming calls can be authenticated using passwords
and Caller ID. A RADIUS client can also be used.
The Telnet configuration can also be protected using the same authentication
methods. Each menu item in the Express XL/XLT has a security level associ-
ated with it. A telnet session is assigned a privilege level which determines
which menu items are accessible to the telnet client. See Security Levels on
page 33 (in Chapter 3) for more information on menu security levels.
Filters can be defined to prevent certain addresses or protocols from being
transferred from LAN-to-WAN, WAN-to-LAN, or WAN-to-WAN.