Cabletron Systems HSIM-F6 - Manual (Page 48)

Chapter 3: Local Management
3-24 HSIM-F6 User’s Guide
3.9.1 Full Duplex FDDI
Full duplex FDDI is the creation of a 200 Mbps point-to-point link
between two FDDI devices that support full duplex FDDI operation. Full
duplex FDDI is a technology where the end devices simultaneously
transmit and receive data at 100 Mbps. For the HSIM-F6 to operate in full
duplex mode, specific criteria must be met. Before configuring the
HSIM-F6 to operate in full duplex mode, ensure that the network
configuration meets the following requirements.
• The FDDI device that connects to the HSIM-F6 must be a Cabletron
Systems product that supports full duplex FDDI (e.g., 9F426-02
MMAC-Plus SmartSwitch module, or another HSIM-F6).
• Full duplex FDDI is a point-to-point link between two devices that
support full duplex operation. No other stations may be present on the
ring. If a third station is added, the HSIM-F6 automatically returns to
standard FDDI operation.
• There must be two FPIMs installed in the HSIM-F6 to connect to the
other full duplex FDDI device. To operate in full duplex mode, one
port transmits data while the other receives data simultaneously.
Cabletron Systems recommends that the connection between the two
devices be made from the A port of one device, to the B port of the
other.
NOTE
Making a connection between the A ports of both devices to
the B ports of both devices (as is done with a DAS in normal
FDDI operation) DOES NOT create a redundant path when
using full duplex FDDI.