Dual-Attached Station - Cabletron Systems 3F00-01 User Manual

Chapter 2: Connecting to the Network

2.1.1 Dual-attached Station

A dual-attached station (DAS) is connected to both the primary and
secondary FDDI rings. This is the preferred configuration, since it
provides the full benefits of dual-ring operation, allowing the network to
continue to operate if a station or cable fails.
Figure 2-1 shows the ATX, with a 3F00-01 installed, connected as a DAS
to two other DASs in an FDDI network. (A and B indicate A port and B
port.) When DAS devices are connected on an FDDI ring, A ports must be
connected to B ports, and B ports must be connected to A ports.
DAS
DAS
A B A
B
A B
ATX
FastNET ATX
PACKET PROCESSING ENGINE
NMS PORT
POWER
FDDI MIC A OPTICAL BYPASS FDDI MIC B
RING A RING B
1876 04
Figure 2-1 Dual-attached Configuration
Page 2-2 FDDI Dual-Attached Intelligent Module User's Guide