System information

5500 Express IP Control Unit
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ports to time slice. However, the 5500 control unit’s WSC is actually two
mini-controllers, each responsible for servicing 4 ports.
Setting the 5500 control unit’s dual mode operation to
Enable allows each
device to obtain quicker service. To maximize performance, balance the load
between the two mini-controllers, dividing your devices equally between ports
0 through 3 and ports 4 through 7.
Using Twinax Multiplexers
The use of twinax multiplexers can prevent and increase in performance.
Multiplexers combine the signals of multiple ports into a single cable for a
longer transmission run. The signals are de-multiplexed into separate ports.
Older multiplexers, such as the IBM 6299, were developed before the
invention of a dual mode WSC. For an older multiplexer to combine all eight
ports of a dual mode WSC, the two mini-controllers must be reconfigured to
function as a single controller. This can result in a loss of performance.
Setting the 5500 control unit’s dual mode operation to
Disable reproduces this
action and can reduce performance.
Instead of decreasing performance, we recommend that you use a new
multiplexer, the IBM 7299. This multiplexer uses time domain multiplexing to
combine the signals from the two active mini-controllers.
5250 Express Data Stream
The independent modes available on the 5250 Express data stream is the
Optimized Mode . It offers point-to-point communications with an Express
device. This mode is ignored by other devices and works in any valid cabling
configuration.
C.5 Using the 5500 Control Unit as a Network Station Boot Server
The 5500 control unit makes a good alternative boot server. This help reduce
network traffic and improves local bootup times. This control unit can be used
at any remote site that does not have a local server. It serves the remote NPT
customers as a great way to improve the function delivered to their remote
sites, allowing twinax NPTs to move to twinax Network Stations without the
need to change cabling.
Using the 5500 control unit as a boot server for IBM Network Stations
requires that you perform NVRAM setup on your Twinax Network Station.
When used in this mode, the NSM (Network Station Manager) configuration
server builds a text file called
defaults.dft . This file is built in the configuration
directory of the client's NSM configuration server, for example:
\nstation\
prodbase\configs.