HP 200 Series Services And Applications page 213

Connection Controls—Manual Adapter
Using the connection method discussed in the previous section, several
connection control parameters are useful in situations in which the
destination is busy and in which connections fail due to problems in the
network itself. These parameters include:
Connect Retry Count
Connect Wait Time
Delay After Connect Failure
Two additional parameters can be used to minimize the connect-time
charges. These include:
Minimum Connect Duration
Connect Inactivity Time
In many locations the telephone company or PTT bills the user one rate for
an initial period of time and a second rate for incremental periods of time.
For example, a telephone company in California bills a user at one rate for
the first three minutes of a call and at a second rate for every additional
minute. Minimum Connect Duration could be used, in this example, for the
first three-minute period, and Connect Inactivity Time could be used for the
incremental one-minute periods.
These parameters, when set to the correct billing periods, cause the router
to monitor data transmission and reception. They serve two important
functions:
First, the user will incur the minimum connect-time charge for data
transmissions. The router will automatically disconnect when data
has not been sent or received for an incremental billing period.
Second, after data has been sent or received, the connection is
maintained until the end of the current billing increment. For
example, suppose a connection is established and data is transferred
for several seconds. Rather than immediately closing the circuit, the
router holds the circuit open until the end (actually, one second
before the end) of the Minimum Connect Duration. This prevents
incurring the cost of another call if additional data is exchanged in
this time period.
Improving Network Availability
Switched Circuit Types
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