3com DUA1800-0AAA04 User Manual

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3-12
C
HAPTER
 3: I
NSTALLING
 M
ODULES
 I
NTO
 T
HE
 MSH C
HASSIS
DUA1800-0AAA04
The ability to allow any MAU or Bridge to be assembled into a 
ring, independent of its physical location.
Signals are retimed when they enter or leave the RingBuilder 
module at RI (Ring-In) and RO (Ring-Out). This increases the 
distances supported on the trunk cables to the next repeater or 
station and simplifies the overall network design.
Isolation logic allows the RingBuilder module, with attached 
MAUs, to act as a stand-alone sub-network. This mode can be 
controlled through management and is helpful for diagnostics 
and fault analysis.
A Fail-Safe mode on RI and RO ports provides highly reliable ring 
operation. If the equipment at the other end of the trunk cable 
(e.g. a RingBuilder in another MSH chassis) provides a compatible 
phantom signal, then the RI and RO ports can be commanded to 
wrap if the phantom signal disappears, protecting the rest of the 
ring from the faulty trunk segment.
The RingBuilder provides the management module with 
information on the network status including alarms and statistics 
traffic.
LEDs provide visual information about ring speed, presence of 
data and the status of the Ring-In and Ring-Out ports.
The MAC Module
A Media Access Control (MAC) module installed on the 
RingBuilder module provides the following:
Monitoring of the health of the main ring
An access point for network management
An optional second MAC module can be fitted to a second 
location to monitor the health of the backup ring.
The user guide that accompanies the optional MAC module will 
give further information.
Chassis.bk : CHAPTER3  Page 12  Monday, February 10, 1997  1:11 PM