PCI FDDI Administrator's Guide

Installing and Configuring PCI FDDI
5 - Connect the Adapter to the Network
Chapter 256
Figure 2-3 Dual Attach Station
• You can also attach the adapter as a DAS (Dual Attach Station)
directly to the adjacent stations in a dual-ring network. Connect one
station’s A port to the neighboring station’s B port, and a station’s B
port to a neighboring station’s A port.
Figure 2-4 Optical Bypass Switch
• With a dual-ring topology, you can also use an Optical Bypass Switch
(OBS) between the adapter and the dual-ring to maintain continuity
of the primary and secondary ring in case of an adapter failure. The
optical bypass switch connects directly to the adapter via A and B
cables pre-attached to the switch. The A cable connects to the
adapter’s A port, and the B cable connects to the adapter’s B port.
The OBS connection is the same as if it were a dual-attach adapter
attaching directly to the dual-ring.