Olicom CrossFire 8600, Руководство по эксплуатации

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CrossFire 8600/8605 Token-Ring Switches v. 1.2, P/N: 710001641 Switch Theory of Operation
faulty packets is high, the store and forward mode is used. This provides optimized
performance but introduces variable latency.
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 8600, a RI/RO-like connection is available on fiber expansion ports
and on ports 19 and 20. On CrossFire 8605, a RI/RO-like connection is possible on
all the 20 fiber ports and on fiber expansion ports.
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
switch port, creates redundant paths because the two switch ports are connected to