Configuration 1 - Multitech MMH900 User Manual

Chapter 2 - Configuration
2.2

Configuration 1

Configuration 1 is two Multi-Tech MultiMux MMH904Ca/144 which are
four channel multiplexers with internal 28.8K bps composite link modems
linking sites one and two over a 4-wire analog lease line. The local site
has the MMH904Ca/288 connected to a host minicomputer. The remote
site has three terminals and a shared printer connected to the
asynchronous channels of the remote mux. At the remote site, the three
terminals are communicating with the remote mux on 38.4K bps
asynchronous channels and the printer is configured for one setting
above its cps rating. Configuration 1 is shown in Figure 2-1.
Figure 2-1. Configuration 1
Channels 1 through 4 at the local site are connected to channels 1
through 4 at the remote site. The asynchronous channels of the local
mux are configured with XON/XOFF software flow control enabled, so
that the channel buffers in the local mux do not lose data from the host.
With flow control enabled at the local mux, the local mux can tell the host
when it feels that it's dynamic buffers are becoming full. For the same
reasoning, pacing should be enabled at the remote site, if it appears that
data is being lost at the terminals. Pacing allows the terminal to tell the
remote mux not to send any more data until its buffers are cleared.
Pacing should also be active for the printer to ensure that all the data is
received by the printer. The first set of parameters in the following
examples are for the local mux and the second set are for the remote
mux.
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