3Com DUA1800-0AAA04 TV Video Accessories User Manual


 
DUA1800-0AAA04
Introduction 3-11
A block of LEDs shows the status of each of the twelve lobes
attached to the module. Another five LEDs provide information
on the state of the module.
The MAU module can operate in two modes:
Enabled Mode - the MAU is connected to a local ring section. All
of the ring-stations connected to the MAU are connected to a
ring comprising a RingBuilder module and any other MAUs
similarly configured to the RingBuilder.
Isolated Mode - the MAU is isolated from the local ring section
and its associated RingBuilder module in stand-alone mode to
form its own ring. Ring-stations can only communicate to other
ring-stations connected to the same MAU module.
The RingBuilder Module
The RingBuilder Module provides the following features:
An interface to an external token ring for its backplane ring via
Ring-In (RI) and Ring-Out (RO) ports.
The interconnection of individual MAU modules into a local ring
section utilizing one of the five token ring buses.
The management interface for all token ring modules located in a
local ring section.
RingBuilder modules can only be connected together by token
ring trunk cables external to the MSH chassis. In addition the
RingBuilder provides the following features:
The speed of the RingBuilder module can be set to operate at 4 or
16 Mbps.
A RingBuilder module is used to create a local ring utilizing one of
the token ring buses. One RingBuilder is required per backplane
ring. Ring selection can be determined either by setting a DIP
switch located on the modules themselves or by management.
Chassis.bk : CHAPTER3 Page 11 Monday, February 10, 1997 1:11 PM