Cabletron Systems BRIM-F6 - Manual (Page 33)

FDDI Devices
BRIM-F6 User’s Guide Page A-9
Figure A-6. Dual Homing Topology
Concentrator 3 in Figure A-6 has redundant connections to the main ring
through either concentrator 1 or 2. The FDDI connection rules only
permit one active connection, Port B. If a cable failure severs concentrator
3’s connection to concentrator 2, CFM activates Port A.
A.6 FDDI Devices
FDDI recognizes four station configurations (SAS, DAS, DAC, and
SAC). These configurations differ by the mix of FDDI entities within the
station (see Figure A-7).
All stations must have:
• one SMT
• at least one MAC
• one PMD
• one PHY.
Port A
Port A Port A
Port B
Port B Port B
Port M Port M Port M Port M
Primary
Connection
Backup
Connection
3
2 1
BRIM-F Book Page 9 Monday, January 29, 1996 9:26 AM