Setting the FDDI Station Type

Supported Station Types

GS2000 line cards can serve as any one of the following FDDI station types:

  • Dual Attachment Station (DAS)

  • Single Attachment Concentrator (SAC)

PHY Port Identification

The FDDI interface is composed of two PHY ports labeled A/M and B/S. The PHY A/M port functions as either an A port or an M port, depending on the line card's station type. Similarly, the PHY B/S port functions as either a B port or an S port. The following table shows the relationship between station type and PHY ports:

If. . . Then. . .
The line card is cabled as a DAS The PHY A/M can be used either as an A port connected to the FDDI ring, or to the M port of a DAC if in a dual homing topology.

PHY B/S can be used either as a B port connected to the FDDI ring, or to the M port of a DAC if in a dual homing topology.

The line card is cabled as a SAC PHY A/M is used as an M port connected to the S port of a SAS.
PHY B/S is an S port connected to the M port of a Dual Attachment Concentrator (DAC).
The line card is cabled as a SAS PHY B/S is an S port connected to the M port of either a SAC or DAC.

PHY A/M is not used.

Setting or Changing the Station Type

The FDDI interface must be configured to reflect the station type for which the physical cables are connected. For example, if the GS2000 line card is cabled to function as a Single Attachment Concentrator, you must set the station type for the interface to SAC. The default installation setting is DAS.

Procedure:

Step Action
1 Select Telnet to Module from the application tree and connect to the GS2000 line card.
2 At the Main prompt (Main>), type Config and press Return.
3 At the Config> prompt, enter interface, followed by a space and the number of the logical interface you want to configure.

Example: Config>interface 10

4 Press Return. The FDDI/n config> prompt is displayed.
5 At the FDDI/n Config> prompt, enter  set station station-type where station-type is das for a Dual Attachment Station, or sac for either a Single Attachment Concentrator or a Single Attachment Station.  The default is das.
6 Press Return. The interface is set as specified, and the FDDI/n config> prompt is displayed.
7 Log out of the Telnet session and terminate the connection.