HP 200 Series Services And Applications page 222

Improving Network Availability
Sample Networks
The static routes defined for the circuit-switching network must
have higher assigned costs than the routes used on the packet-
switching network but equal preference. Thus, packet-switched
routes are selected over circuit-switched routes to maximize
throughput and minimize cost.
Detailed configurations for this network example are available from
HP on request.
Bandwidth on Demand
HP routers support V.25 bis extensions defined by Cisco Systems, Inc., and
Ascend Communications, Inc. The extensions allow control of several
parameters used for establishing communications on ISDN networks. The
inverse multiplexer parameters that can be controlled by HP routers include:
Per-channel bandwidth (56 Kbit/s, 64 Kbit/s, etc.)
Minimum channels to aggregate (the minimum number of ISDN
channels to open when data is available).
Maximum channels to aggregate (the maximum number of channels
to open regardless of the amount of data to transmit).
Figure 15. Inverse Multiplexers Used for Bandwidth on Demand
Figure 15 shows two routers that are connected to inverse multiplexers that
are attached to an ISDN network. The inverse multiplexers open circuits as
needed. When the traffic volume from the routers increases, additional
circuits are opened. As the traffic volume decreases, circuits are closed.
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Inverse Multiplexers
ISDN