10
MINISTAT-FOUR
2.2 Typical Applications
Figure 2-1 shows a typical application. The MiniStat-Four concentrates data coming
into its sub-channels at various rates from a host computer. It then statistically
multiplexes sub-channel data to form a composite data stream with a rate much
smaller than the arithmetical sum of the individual sub-channel rates.
Figure 2-1. Typical MiniStat-Four application.
The required composite link rate depends on MiniStat-Four buffer capacity versus
sub-channel traffic statistics and allowable delay. The composite data is sent
through modems to the remote MiniStat-Four, where it is demultiplexed and
distributed to the local users at their nominal rate (which may differ from the
nominal transmission rate).
NOTE
Reliable operation of any statistical multiplexor requires the equipment
connected to its sub-channels to use some form of flow control.
However, the flow-control method used at each of the two sub-channel
ends can differ (hardware control at one end, software control at the
other end), and the conversion is transparently performed by the
MiniStat-Four.
KEY
19.2 = 19.2 kbps
9.6 = 9.6 kbps
4.8 = 4.8 kbps
2.4 = 2.4 kbps
1.2 = 1.2 kbps
D = DTR flow control
X = X-ON/X-OFF flow control
19.2 X
19.2 X
1.2 D
2.4 X
19.2 X
19.2 D
9.6 D
4.8 X
MiniStat-
Four
MiniStat-
Four
Modem
Modem
Terminal
Modem
Modem
Terminal
Printers
