A And B Keying - Cabletron Systems 3F00-01 User Manual

Chapter 2: Connecting to the Network

2.3.1 A and B Keying

To install the ATX as a DAS, the preferred configuration, a MIC A and
MIC B are required.
Figure 2-7 shows the keying scheme used to differentiate A and B MICs,
which are identified on the 3F00-01 and 3F55-01 front panel as FDDI
MIC A and FDDI MIC B respectively.
B
I M I C
F D D
A
I M I C
F D D
B Keyed MIC plug
and Receptacle
Key Slot
A Keyed MIC plug
and Receptacle
1876 10
Figure 2-7 MIC A and MIC B Keying
Looking into the open end of the receptacle, an A key slot is to the left of
the horizontal center of the MIC and a B key slot is to the right of the MIC
center. The arrows indicate how the plug mates to the receptacle.
Note: If you are making a fiber cable assembly to connect FDDI DAS
devices, the MIC plug on one end must be keyed as a MIC A, and the MIC
plug on the other end must be keyed as a MIC B. This will help ensure
that devices are correctly connected. Also, FDDI terminations should
always be labeled for connection to port A or port B.
FDDI Dual-Attached Intelligent Module User's Guide Page 2-9