Cabletron Systems MRXI-22 User Manual - page 9

INTRODUCTION

1-3

The MRXI fully conforms to the IEEE 802.3 Repeater, AUI, and 

10BASE-T specifications, and provides the flexibility to connect 

networks using IEEE 802.3, Ethernet Version 1 or Version 2 equipment. A 

Repeater Interface Controller (RIC) in the MRXI provides full 802.3 

repeater capabilities integrated into a single chip. The MRXI transmits 

re-timed data packets, regenerates the preamble, extends fragments, and 

arbitrates collisions.

The MRXI automatically partitions problem segments, and reconnects 

non-problem segments to the network. This feature minimizes the impact 

on network operation resulting from a problem on one segment by 

isolating the problem segment. Only devices on the problem segment are 

affected. When the problem is solved, the MRXI automatically reconnects 

the isolated segment to the network.

Since the MRXI utilizes polarity detection and correction, the twisted pair 

connections are not sensitive to signal polarity. The network will still 

function properly with the (+) and (–) lines within a pair reversed. 

Operating in this condition is not recommended and if this condition is 

discovered, the segment should be removed from the network and wired 

correctly by a technician. This reduces the potential for problems in the 

future if equipment changes are made. Connector pinouts are provided in 

Chapter 2, 

Installation Requirements / Specifications

. 

You can configure the two front panel serial ports to support an SNMP 

proxy for Uninterruptible Power Supplies (UPS) or the Serial Line 

Internet Protocol (SLIP). MIB II and RMON support are built into the 

MRXI for network analyzer functionality. In addition, Cabletron’s 

Distributed LAN Monitor (DLM), a software option for the MRXI, 

provides a method for locally polling and monitoring devices on a LAN to 

minimize network management traffic on an enterprise, campus, or wide 

area network.

The MRXI uses Flash EEPROMs that allow you to download new and 

updated firmware using Cabletron Systems Remote 

LANVIEW/Windows, version 2.3 or later or any device using BOOTP or 

TFTP protocols.

The front panel of the MRXI also has a reset switch to initialize the 

processor.