Cisco CATALYST 3920 24 PORT TOKEN RING SWITCH Specification Guide
System Architecture
Catalyst 3920 Token Ring Switch User Guide
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The Cisco RPS supports quasi-redundant and fully redundant configurations in the following ways:
•
In a quasi-redundant configuration, the internal power supply of the Catalyst 3900 is considered
the main supply. Using a one-to-one cable, you connect a single DC output of the RPS to the
Catalyst 3920. The RPS continually monitors the status of the main supply. If the main supply
falls below a set voltage, the RPS intervenes and begins providing power to the switch. When the
Catalyst 3920 power supply is changed from the main supply to the RPS, the switch will reset.
the main supply. Using a one-to-one cable, you connect a single DC output of the RPS to the
Catalyst 3920. The RPS continually monitors the status of the main supply. If the main supply
falls below a set voltage, the RPS intervenes and begins providing power to the switch. When the
Catalyst 3920 power supply is changed from the main supply to the RPS, the switch will reset.
•
In a fully-redundant configuration, all power is supplied by the RPS; the internal power supply
of the Catalyst 3920 is not used. Using a two-to-one cable, you connect two of the RPS DC output
to the Catalyst 3920. The two-to-one cable is a Y-shaped cable with two connectors at one end
of the cable and one connector at the other end. The two connectors at one end of the Y-shaped
cable connect to two DC output power modules. The other end of the cable connects to one
external device, such as the Catalyst 3920.
of the Catalyst 3920 is not used. Using a two-to-one cable, you connect two of the RPS DC output
to the Catalyst 3920. The two-to-one cable is a Y-shaped cable with two connectors at one end
of the cable and one connector at the other end. The two connectors at one end of the Y-shaped
cable connect to two DC output power modules. The other end of the cable connects to one
external device, such as the Catalyst 3920.
Caution
If a fully-redundant configuration is used, do not connect the AC power cord to the
Catalyst 3920 as this may cause damage to the Catalyst 3920 or the RPS.
There are three status indicators for the RPS: RPS PRESENT, RPS GOOD, INT PS GOOD. See
“Hardware Troubleshooting” for more information about the status indicators.
“Hardware Troubleshooting” for more information about the status indicators.
For more information about the Cisco RPS, see the Cisco RPS Hardware Installation Guide.
EIA 232 Port
This 9-pin, male management port located on the back of the switch functions as a DTE port.
This port enables attachment of a terminal or terminal emulator that is used to customize the
configuration of the switch, monitor switch activity and status, and test the switch. Console access
can be either local, by direct attachment to the EIA 232 port, or remote, through a modem
connection.
configuration of the switch, monitor switch activity and status, and test the switch. Console access
can be either local, by direct attachment to the EIA 232 port, or remote, through a modem
connection.
The EIA 232 port automatically detects the baud rate of the terminal to which it is attached.
System Architecture
The internal components that comprise the system architecture of the Catalyst 3920 handle the
processing and switching of the frames. The principle components are described in this section.
processing and switching of the frames. The principle components are described in this section.