15
Chapter 2
Installation
CentreCOM Multiport Hub
AT-3600 Series Repeaters act as IEEE 802.3 compliant Ethernet compatible
installations. They support multiple stations on the network and have an
additional network port for an AUI or other media appliqué to enable
connection to the network’s main Ethernet backbone. An RS232 port allows
connection to an asynchronous terminal or PC with terminal emulation for
hub management.
Each repeater also provides an interface to the Ethernet network that
supports TCP/IP, SNMP and related protocols. The Omega software enables
loading software updates across the network. The model AT-S4 Firmware
Cassette is available for installing software backups and updates.
AT-3600 Series Repeaters also implement an interprocessor interface that
allows up to 8 repeaters to be cascaded together in a single department
concentrator chassis. When operating in such a multiprocessor configuration,
the
management agent software
manages all modules in the chassis. For the
purposes of network topology analysis, all repeater modules combined in a
department concentrator chassis collectively count as just one repeater.
Master Module
The uppermost manageable AT-3600 module in a chassis performs all
management reporting activities and is referred to as the
Master
. The other
AT-3600 modules in the same chassis are called
Slaves
. Modules are
numbered from 1 through 8, top to bottom, in the chassis. The Master is
defined as the module in the lowest-numbered (physically topmost) occupied
slot position. Typically this is slot 1, but it could be slot 2 if slot 1 is vacant.
Slave modules may occupy any other higher-numbered (physically lower) slot
position. Such Slave modules do not need to be in contiguous slots because
they are managed through a backplane that extends the full height of the
chassis.
Backup Module
The next manageable module in the chassis communicates with the Master
and can take over the Master’s functions if necessary. This special module is
called the
Backup
and always occupies the next higher-numbered slot
position in the chassis (i.e., physically below the Master).