AT&T 555-230-223 manual System Software

The DEFINITY LAN Gateway system assembly can be distinguished from the DEFINITY AUDIX system assembly by the ‘‘TN’’ codes on the circuit packs and by a DEFINITY LAN Gateway label. The DEFINITY AUDIX system assembly uses TN566 (not shipped on new systems), TN566B, TN567, and TN2169 or TN2170. The DEFINITY LAN Gateway system assembly uses TN2170 and TN2208.

The TN2170 circuit pack supports a hard disk, Ethernet controller, and removable media. It also supports a serial port, an additional analog modem port, and remote maintenance hardware.

The TN2208 circuit pack supports a 32Mhz 486SLC Central Processing Unit (CPU) with 16MB of fixed (non-socketed) memory. It has 2 serial ports and a user interface/Liquid Crystal Display (LCD) panel. Naturally, it also has an interface to DEFINITY call control and switching fabric.

System Software

The software that provides the DEFINITY LAN Gateway application on the system assembly comes preloaded on the system when it is shipped from the factory. It is also supplied on removable media that can be reinstalled or used to upgrade an existing system.

The function of the software is to act as a mapper (or brouter) for ASAI messages. It links an ISDN network (DEFINITY call control) to a TCP/IP network (computer client) by moving ASAI messages back and forth from Q.921 synchronous data frames to TCP/IP Ethernet packets. It also associates computer clients (by their TCP/IP network addresses) to physical ports on DEFINITY that are administered as ASAI extensions.

This mapping provides a virtual point-to-point connection between a particular computer client and an associated port on DEFINITY. This arrangement continues to support the ASAI ability to sense when a particular computer client connection is lost and send an alarm. It also provides a more secure environment by fixing the addresses of the clients that may receive DEFINITY LAN Gateway service.

1-4Issue 1 January 1996