Flow Control; Address Tables And Limitations - Bay Networks 58000 Installation And Reference Manual

Flow Control

Address Tables and Limitations

893-878-B
The Model 58000 switch uses a proprietary flow-control feature on 100 Mb/s
full-duplex links to control traffic and avoid congestion on the link. If the
receive port buffer becomes full, the Model 58000 switch issues a flow-control
signal to the device at the other end of the link to suspend transmission. When
the receive buffer is no longer full, the Model 58000 switch issues a signal to
the end station to resume the transmission.
These flow-control signals may not be supported by other vendors' full-duplex
product implementations, so be aware of possible problems when congestion
occurs on the ports operating in this mode. Typically, these flow-control signals
are interpreted as CRC errors, but they should have no greater impact on the
receiving device.
If you experience interoperability problems with other vendors' equipment
while using the full-duplex implementation, disable flow control on the
100 Mb/s full-duplex port connected to the interoperable device. If the problem
persists, reconfigure the associated Model 58000 switch (and the adapter card
installed in the attached station) for half-duplex operation. For instructions on
how to disable and enable flow control, refer to
in Chapter 6, "Configuring the Model 58000 Switch."
Network traffic typically includes frames between hosts, printers, and file
servers and the user end stations that access them most frequently. The primary
job of the Model 58000 switch is to deliver frames rapidly between these
network devices by "switching" the network traffic from segment to segment.
The Model 58000 switch enables this switching capability by tracking the MAC
addresses associated with each physical device that sends frames through its
ports. When a Model 58000 switch receives a frame, it "learns" each address and
adds the address to its address table. Once the address of a particular device is
learned, the Model 58000 switch automatically switches incoming frames
addressed to that device directly to the switch port where the device is connected.
Model 58000 Switch Operation
Modifying Port Configurations
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