Avaya Interaction Center, Руководство программиста

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The asynchronous nature of the system
Issue 2.1 August 2003 25
The asynchronous nature of the system
The asynchronous design of Avaya Computer Telephony for IC presents situations that
must be anticipated by connected applications.
While some requests are processed locally, others may involve distributed components of
the Telephony system. These distributed components may be connected through a LAN or
a WAN. Some requests may wait for another user’s response or for communication delays
in a phone system.
All applications that process events must be designed to manage these situations. For
example,
VDUChange
events may be reported from various sources at various times in
any order.
In general, applications should not make a request and postpone all other operations until
the response to that request is received. For example, if
Logout
and
Exit
commands
arrive at VTel just before a
MakeCall
request, the application may never receive a
response, since VTel will no longer be available.
Designing for asynchronous processes is more difficult than designing for synchronous
processes, and requires careful attention during the initial application design.Most
applications are generally more complex than originally envisioned.
When programming asynchronous processes, you may want to:
●
establish queues for both requests and events
●
affix a unique identifier to each request to allow its response to be easily distinguished
from others
●
use time outs to allow your application to recover from problems elsewhere