chapter24

CALL ACCOUNTING SYSTEMS
All PBXs, most hybrids, and many key telephone systems include a CDR port that
receives call details at the conclusion of each call. The call details can be printed
or passed to a call accounting system for further processing. The CDR output of
most systems is of little value by itself because calls are presented in order of completion
and lack rates, identification of the called number, and other such details
needed for control of long distance costs. Call accounting systems add details to
create management reports, a complete long distance statement for each user, and
departmental summaries. The primary purposes of a call accounting system are to
discourage unauthorized use and to distribute costs to users. They also have other
uses in some companies. For example, a supervisor may use the CDR record to
check the effectiveness of an employee’s outgoing sales calls.
Most call accounting systems on the market are software programs for PCs.
CDR data either feeds directly into an on-line PC or it feeds into a buffer that
stores call details until it is polled. A buffer makes it unnecessary to tie up a PC in
collecting call details. If the power fails, the battery backup in the buffer retains
the stored information.
In multi-PBX environments, a networked call accounting system may be
required. These systems use buffers or computers to collect information at remote
sites and upload it to a central processor at the end of the collection interval.
If long distance calls can be placed from one PBX over trunks attached to another,
a tie line reconciliation program may be needed. The tie line reconciliation
program uses the completion time of calls to match calls that originate on one
PBX and terminate on trunks connected to another. Networked PBXs send originating
station identification over the signaling channel to a remote PBX. If the
remote PBX is equipped to extract the calling station identification from the
network and associate it with the CDR output, the need for tie line reconciliation
is eliminated.
Most PBXs can output to the CDR port any combination of long distance,
local, outgoing, and incoming calls. The amount of detail to collect is a matter of
individual judgment, but sufficient buffer and disk storage space must be provided
to hold all the information collected.
CALL ACCOUNTING APPLICATION ISSUES
Application information for PBXs and key systems is included in the next two
chapters. This section covers application information for call accounting systems.
Call Accounting Evaluation
Most PBXs today are purchased with a call accounting system that is normally
programmed and supported by a third-party manufacturer. The following are
some criteria for selecting a call accounting system.
Reports
The main reason for buying a call accounting system is for its reports. Evaluate
factors such as these:
_ What kinds of special reports are provided? Do they meet the
organization’s requirements? Examples are unused extensions,
long or short duration calls, unused trunks, and calls to emergency
numbers.
_ Can reports be distributed over the Internet or a company intranet?
_ Can users access their reports with a browser?
_ Are custom-designed reports possible?
_ Is it possible to export report information to an external program, such
as a spreadsheet or database management system, to produce custom
reports?
_ Are traffic reports produced? If so, are they accurate?
_ Are management reports, such as inventories, provided?
_ What kind of manual effort is needed to produce reports? Does it
require a trained operator, or can clerical people perform the month-end
operations with little or no formal training?
_ Is tie line reconciliation required? If so, does the manufacturer support it?
Operational Issues
Most call accounting systems are not completely automatic. The functions
required are downloading the call data from buffers (if they are used), rating calls,
and producing end-of-period reports. The most effective systems provide dragand-
drop capabilities for setting up and scheduling reports and distributing them
to users.
Features
Many call accounting systems provide features that are of extra value. Common
features are toll fraud alerts, telephone directory, and equipment inventory. Some
high-end systems offer telemanagement packages, which typically include service
orders, repair, and inventory in addition to directory and call accounting.
Vendor Support
As with most software packages, vendor support is important for installing and
maintaining the system. Evaluate the vendor’s experience in supporting the package.
Determine whether the vendor has people who have been specifically
trained. Evaluate the amount of support the package developer has available and
what it costs. Some vendors sell ongoing support packages, and where these are
available, the cost-effectiveness should be evaluated.
Call Rating
Most call accounting packages have call-rating tables based on V&H (vertical and
horizontal) tables. These divide the United States and Canada into a grid from
which point-to-point mileage is calculated. Tables must be updated regularly as
rates change. Also, consider that many companies do not need absolute rate accuracy.
To distribute costs among organizational units, precision is usually not
required. Many long distance rate plans use rates that are not distance sensitive,
so V&H rating accuracy is not required. The rating tables identify the called location,
so if rating tables are not used, the called city and state will not be printed on
toll statements unless the vendor offers an abbreviated table. Determine facts such
as these:
_ What kind of rating tables does the manufacturer support?
_ How frequently are tables updated?
_ What do updates cost?
_ What IXCs’ rates does the package support?
_ How are intrastate rates calculated?
_ Do you need to bill back to user departments with high accuracy?
Capacity
Call storage equipment is intended to maintain information on a certain number
of calls. When buffer storage is full, it must be unloaded and calls processed.
Usually, the system must store at least 1 month’s worth of calls. Evaluate questions
such as these:
_ How much storage space is required?
_ What is the capacity in number of calls, both incoming and outgoing?
_ How much growth capacity is provided?
_ Is storage nonvolatile, so if power fails calls are not