9000

38 Chapter 2

Installing the HP EISA FDDI/9000 Adapter

Connecting the Adapter to the Network

Dual-Attachment MIC Adapter Connections

This section illustrates the dual-attachment MIC adapter connections.

There are two ways to connect the adapter to the FDDI network. It can

be connected directly to the adjacent stations in a dual-ring network or to

a concentrator (DAC or SAC), typically dual-homed for additional fault

tolerance. You can use an Optical Bypass Switch (OBS) between the

adapter and the dual ring. An OBS maintains continuity of the primary

and secondary ring when the station is powered down, or in the event of

an adapter failure.

Signals must be routed such that the primary Tx output from each

station is routed to the primary Rx input of its neighbors, and the

secondary Tx output is routed to the secondary Rx input of the other

neighbor, and so forth, as shown in Figure 2-2.

Figure 2-4 Dual-Ring Tx/Rx Topology

MIC connectors are individually keyed to ﬁt type A or type B ports. The

key is located in the slot on one side of the connector. Be sure the key

type of the plug matches the port type on the adapter.

Port A

Port B

Tx Secondary

Rx Primary

Tx Primary

Rx Secondary

FDDI Adapter

Port A

Port B

Tx Secondary

Rx Primary

Tx Primary

Rx Secondary

FDDI Adapter

FDDI

Network

Port A of

neighbor station

Port B of

neighbor station