Cabletron Systems TRMM-2, User Manual

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INTRODUCTION TO MULTIPLE-RING MMAC FUNCTIONALITY
A-4
A.3.1 Single Ring Versus Port Assignment Management
Modules
A single ring management module can only manage one ring. A mid-slot
management module must be installed to manage each additional ring.
The use of mid-slot management modules reduces the slots available for
other MIMs. The TRMM-2 and TRMM-4 can manage multiple rings
without using additional MIM slots.
A.3.2 Mixing Single Ring And Port Switching MIMs
Single ring MIMs and port switching MIMs are compatible and
interconnectable across FNB Ring 1; however, as shown in
Figure A-3 ,
single ring MIMs cannot communicate with FNB Rings 2, 3, or 4.
Installing a single ring MIM between port switching MIMs stops
communication on FNB Rings 2, 3, and 4, splitting these rings into
separate Token Rings on either side of the single ring MIM. Therefore, it
is recommended that all port switching MIMs be grouped together in the
right-most MIM-slots.
Single ring MIMs can still segment FNB Ring 1, as shown in Figure A-3 .
They view the FNB as having only one ring and are not affected by the
use of FNB Rings 2, 3, or 4.
A.4 AVAILABLE RINGS
This section describes the rings that can be used in port switching
configurations. They are:
•
FNB rings
•
Auxiliary rings
• Bypassed rings
A.4.1 FNB Rings
Each port can insert into one of the four FNB Rings (described in
Section A.2.1 ). Each ring is an independent Token Ring. Use a device
such as a switch or router to allow users on different FNB rings to
communicate.