Assessing Processing Requirements for Interactive Voice Response Applications
Original Publication Date: 1997-May-01
Included in the Prior Art Database: 2005-Apr-01
A key factor which prospective purchasers of Interactive Voice Response (IVR) systems consider is the total number of simultaneous telephone calls that the system can handle.
Assessing Processing Requirements for Interactive Voice
A key factor
which prospective purchasers of Interactive Voice
Response (IVR) systems consider is the total number of simultaneous
telephone calls that the system can handle.
telephone exchange, where the limitation is generally
based on the "wiring", the limiting factor in IVR systems is normally
the processor Central Processing Unit (CPU) and Input/Output (I/O)
because a typical IVR application requires access to a
large number of pre-recorded and digitized voice phrases (segments)
and to other resources; e.g., a remote database server - in order to
carry out a transaction with a caller. The processing power required
during one telephone call to access these resources can be very
of IVR applications is huge. They range
simple playback of one message (e.g., a weather forecast) to complex
'office' systems handling voicemail messages, paging systems, call
forwarding, directory services, user options, etc., all on the same
system suppliers offer a range of processors, the most
powerful of which may typically be ten times as powerful as the least
powerful. Purchase prices will, if anything, show a greater spread.
desirable to assess the processing requirements of an
IVR system realistically, since excess telephone lines or excessively
powerful processors will be over-priced and uncompetitive.
The described approach uses the following data:
1. Published comparable processor and I/O subsystem performance
benchmarks for each system, e.g., the "Spec" and/or "TPC"
2. Comparable performance measurements, on a "base" IVR system,
of each type of IVR activity, e.g., for each of: voice
recording, voice playback, speech recognition, external host
access, compression algorithms, etc. Durations must also be
carefully controlled and recorded.
3. Detailed information on calls:
o Average call length (or list of lengths if a number
of very different IVR applications are to be used)
o Per-call count and timings for such as recordings,
database accesses, listening to menus, entering data
on phone keypad, speech recognition events, etc.
4. Detailed costs of all software and hardware components.
Typically, an IVR system has a base price plus hardware
price per telephone line plus software licence per
The following steps are then performed using this data:
o Construct database of machines versus performance benchmarks