User`s guide

and the manual disconnect in the SLTALink Manager, this scenario does not result
in the application terminating. This scenario therefore carries the same advantages
and disadvantages as those described in the previous paragraph.
Monitoring: Application Termination Strategy
There are three strategies for terminating the remote LNS monitoring application.
The first strategy is to require user intervention to shut down or terminate the
application. No special software must be written for this case. For the dial-in to a
network scenario when the call is user initiated, the user is presumably available to
shut down or terminate the application. In the dial-out case, the requirement of user
intervention to terminate the application means that every call from a network is
seen by an user.
If the network is sending alarms, user intervention is highly
desirable.
The second approach requires a node on the network to send a network variable
update to the host when the network no longer requires the host application to be up
and running. When the host application receives this network variable, it should
enter a shut-down routine. This approach places the responsibility on the network to
determine when the host application is needed and requires a hook in the monitoring
application, but provides a level of automation when dial-out is used.
The third approach is the most blunt. In this scenario, the remote host application
terminates itself either after completing a series of actions or based on a timer.
We
do not recommend this scenario for the general scenario, but it has certain appeal for
some applications. For example, a connection may be established through dial-in or
dial-out based on a timer. The host application could then take a series of
measurements from the network, log them to a file, and then terminate itself.
Monitoring: Missing Messages atier a Dial-Out
In general, the message that triggers a dial-out from the SLTA-10 on the network to
a remote PC host is lost.
When a network variable update is sent to the SLTA-10 Adapter and no phone
connection is currently up and running, the SLTA-10 Adapter is typically configured
to dial-out to the host. On the remote PC host, the incoming call is answered by the
SLTALink Manager application. The SLTALink Manager then reads the Remote
Identifier in the SLTA-10 Adapter and searches through all the .slO files for a match.
The SLTALink Manager application then typically launches the application listed in
the link with optional command line arguments available, for example, to open the
correct LNS database with the correct device name. The process of opening the LNS
application results in the buffers of the SLTA-10 Adapter being over-written; thus,
the original message is lost. Since this message network variable update is by
definition important enough to warrant establishing a connection to the host, a
system strategy is required so that this data reaches the host.
The two basic system strategies are: (1) to have the node on the network continue to
send out the network variable update until the host application sends a message to
the node telling it to stop, or (2) to have the host application seek out the information
upon being launched. The first approach places the burden on nodes in the network,
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SLTA-10 NSI Mode Software