Olicom CrossFire 8730, Reference Manual

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CrossFire 8730 Switch Reference Guide, DOC-7047 v. 1.1 Switch Overview
Token-Ring
The following sections “Token-Ring Port Operation Modes”, “RI/RO-Like
Connection”, “Transmission Priority Queues”, and “CrossLink Connections”
contains information that only applies to the Token-Ring ports.
Token-Ring Port Operation Modes
Each Token-Ring port may operate in one of the following modes:
•
Half-duplex concentrator port
The port behaves like an active MAU port for classical Token-Ring. Connects
to a single station in half-duplex mode. This is also known as Token Passing
(TKP) port mode.
•
Half-duplex station emulation
The port is connected to a port on a MAU. Connects to a classical Token-Ring
segment with multiple stations. This is also known as Token Passing (TKP)
station mode.
•
Full-duplex concentrator port
Connects to a single station or to another switch in full-duplex mode. This is
also known as Transmit Immediate (TXI) port mode.
•
Full-duplex station emulation
Connects to another Token-Ring switch. This is also known as Transmit
Immediate (TXI) station mode.
•
RI/RO-like connection
The mode of operation can be configured manually or sensed automatically with
the exception of RI/RO, when equipment is connected to the port. The media speed
(4 or 16 Mbps) can also be manually configured or automatically sensed in all port
modes.
RI/RO-Like Connection
On CrossFire 8730, a RI/RO-like connection is available on ports 19 and 20.
This feature allows the switch to connect to CAU/LAM systems using the RI/RO
connections thus providing a RI/RO-like functionality. This enables the switch to
be easily installed in existing Token-Ring networks.
A loop-back function has been implemented on these ports so that if the port is
disabled or the switch is powered off there will not be a break in the attached main
ring. This means that attaching a cable from the RI port of a MAU port to one of
the two switch ports in effect joins the primary and the backup ring in a MAU/CAU
main ring system. Connecting the other end of the RI/RO connection to the other