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MINIATURE 2-CHANNEL STATISTICAL MULTIPLEXOR
3.2 Typical Application
Figure 3-1 shows a typical Multiplexor application. In this application, the
Multiplexor sub-channels receive data provided by the host computer via channels
operating at various rates, and statistically multiplexes the sub-channel data to form
a composite data stream having a rate much smaller than the arithmetical sum of
the individual sub-channel rates. The required composite link rate depends on
Multiplexor buffer capacity versus sub-channel traffic statistics and allowable delay.
The composite data is sent via modems to the remote Multiplexor, where it is
demultiplexed and distributed to the local users, at their nominal rate (that may
differ from the nominal host transmission rate).
Figure 3-1. Typical Application.
Reliable operation of any statistical multiplexor requires the equipment
connected to its sub-channels to use some form of flow control. However, an
important feature of the Multiplexor is that the flow-control methods used at
each of the two sub-channel ends can be different (hardware control at one end,
software control at the other end), the conversion being transparently performed
by the Multiplexor.
Async
19.2
kbps
19.2
kbps
Mux
Mux
Sync
Modem
Sync
Modem
