DECconcentrator 900MX

This document is an Installation and Configuration manual for the DECconcentrator 900MX module, a six-port FDDI concentrator released by Digital Equipment Corporation in May 1994.

The manual describes how to:

• Install and Remove the module into a DEChub 900 MultiSwitch or a DEChub ONE docking station, highlighting its hot-swap capability.
• Configure the module using a setup port connected to a terminal or PC. This includes setting SNMP parameters, managing IP addresses for in-band and out-of-band management, and performing firmware upgrades.
• Replace Modular Physical Media Dependent (ModPMD) ports, a procedure intended for qualified service personnel.
• Troubleshoot issues using the module's LED indicators and detailed loopback testing procedures.

It also provides technical specifications such as operating environment, physical dimensions, power requirements, and connector pin assignments for multimode fiber (MMF), single-mode fiber (SMF), and twisted-pair (TP-FDDI) cables, as well as an Optical Bypass Relay (OBR) connector. Safety warnings regarding laser light and electrostatic discharge are included.