3Com DUA1800-0AAA04 TV Video Accessories User Manual


 
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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