Installation guide

4-76 Cisco 4000 Series Installation Guide
Network Connection Considerations
FDDI Connections
Multimode FDDI network processor modules provide either a dual-attachment station
(DAS) or a single-attachment station (SAS). Single-mode FDDI network processor
modules provide a DAS. Following are the available FDDI module options:
• Multimode dual-attachment
• Multimode single-attachment
• Single-mode dual-attachment
The multimode FDDI network processor module consists of two cards, each with a
multimode transceiver, with one card fitting on top of the other. The bottom card is the SAS
and contains the physical sublayer (PHY)-A port. If the DAS option is included, the PHY-B
port is located on the module’s top card.
Distance Limitations for FDDI Connections
The distance limitations for single-mode and multimode FDDI stations are shown in
Table 4-7. If the distance between two connected stations is greater than the maximum
distance shown, significant signal loss can result. The single-mode transmitter and the
multimode transceiver each provide 11 decibels of optical power.
Table 4-7 FDDI Maximum Transmission Distances
FDDI Cable Connections
Older versions of the single-mode network processor module (version 2 or earlier as shown
using the show controller Cisco IOS command) use simplex FC-type connectors (see
Figure 4-29 and Figure 4-33) for the transmit and receive ports. Newer versions of the
single-mode network processor module use simplex SC-type connectors. (See Figure 4-30
Transceiver Type Maximum Distance Between Stations
Single-mode Up to 6 miles (10 kilometers)
Multimode Up to 1.2 miles (1.9 kilometers)