IBM 8270, Installation And Service Manual

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Token-Ring Ports
Depending upon the type and quantity of UFCs installed, the 8270-800 can provide
up to 30 Token-Ring ports, the 8270-600 can support up to 24 ports. This
configuration requires 4-port UTP/STP UFCs. The 4-port UFC provides shielded
RJ-45 connectors for the Token-Ring connections.
Note: (8270-800 Only) Ports 3 and 4 on UFC slot 1 are not available for use.
When a 4-port UFC is installed in slot 1, the invalid slot message (X) appears in the
Status display. Even though the invalid slot message is displayed, the 4-port UFC
will operate correctly for ports 1 and 2.
Token-ring ports allow HDX or FDX connections to other switches, hubs, or end
nodes. The ports can be connected to the IBM Cabling System via 150-ohm, STP,
or 100-ohm or 120-ohm twisted-pair (shielded or unshielded).
You can also use optical fiber Token-Ring ports provided by the 2-port Fiber
Token-Ring UFC. These ports are compatible with RI/RO ports and make
connection to the network through ST**-compatible optical receptacles and
multimode optical fiber cables. Since this UFC has only 2 ports, it is valid for
installation in slot 1 of the 8270-800.
The 8270 automatically senses the following types of Token-Ring connection on
each port:
¹
Shared-media segment via a Token-Ring concentrator
¹
Another Token-Ring switch
¹
4-Mbps or 16-Mbps, Token-Ring segment
¹
Dedicated- or shared-media segment, directly to a Token-Ring LAN station
¹
HDX mode
¹
FDX mode
The 8270 automatically configures (requiring no operator action) each port to
operate at the highest level of capability possible. No special crossover cables are
required for Token-Ring stations on dedicated-media segments or for
switch-to-switch connections. These connections use the same cabling used to
connect the 8270 port to shared-media segments. You can configure the 8270 to
override this auto-sense and auto-configure capability through the console
configurator.
UFC Status LEDs
8270 UFCs have OK and Fault (unlabeled) status LEDs. The meaning of these
LEDs is similar to those on the Token-Ring Processor Card. Refer to the
documentation provided with the UFC for details regarding these LEDs.
UFC Port LEDs
In addition to the status indicators, UFCs have LEDs that show the status of the
ports provided by the UFC. Table 1-3 on page 1-10 provides the meaning of the
port LEDs on the Token-Ring UFCs.
Chapter 1. Physical Characteristics and Features
1-9