Billing Q&A with Jim O'Neill

Q—We have an older billing system and are having problems determining the best way to more quickly identify the thousands of call detail records that can’t be associated with a customer account. Upper management says to keep expanding our network facilities, but we just cannot afford a new billing system. What can we do without replacing the entire system?

A—Very good question, and one that has plagued more than one telecommunications company. While you did not indicate the size of your company, or the industry segment, the fact that you are in network expansion mode indicates that you are in a growth area.
If you cannot replace the core system that deals with managing customer accounts, rating the calls and getting invoices out the door, you can consider replacing the interface to the network where the call records are generated and let a mediation platform deal with a whole host of issues.

While many newer systems have fully integrated mediation processes, there are standalone products that can effectively manage raw network usage for you.

The primary focus of mediation includes the ability to:

• Capture all records recorded on the network

• Confirm that there are no recording or transmission gaps

• Identify all billable events

• Edit each billable record for required fields (data from the switch)

• Reformat or normalize records into a format required by the billing system

• Confirm that they can be guided to a customer account and rated based on the calling and called telephone numbers

• Manage usage data from external sources

• Produce reports to support each of these functions.

Mediation products may also include such features as:

• Feeding usage information to platforms for managing prepaid accounts, fraud or network capacity

• Creating secondary destination records for wholesale billing, reseller support, data mining, churn management or archived databases of all recorded events

• Network provisioning of new or modified services.

Not all commercially available products do everything listed above; you should look for one with the best mix of these features. Let’s examine some of them in a bit more detail.

Capturing All Records

Usage data may be extracted from network switches in a variety of ways. The traditional method is batch, whereby CDRs are accumulated on internal hard disks or magnetic tapes controlled by the switch. Depending on volumes and transmission method, a batch could be one or more days or as little as five minutes’ worth of traffic. Periodically batches are extracted (manually or automatically, depending on the switch and recording method) and forwarded to billing mediation.

As networks are becoming more intelligent, and the need for immediate examination of records to detect fraud has grown to near real-time or very frequent, transmission techniques have evolved. To support prepaid customers, the switch has to monitor their usage in real time while the call is in progress. Near real-time call capture is also often employed where there is an ongoing relationship with the customer who has authorized automatic recharging of a prepaid account whenever a low balance is detected.

Editing Call Detail Records

A number of edits might be performed by mediation. The first is to ensure that all events recorded on the switch are extracted. Depending on the switch and transmission method, records may be sent individually, in blocks or in files containing multiple blocks. Editing should ensure that there are no measurable gaps in the information received from the network. This may be done by generating reports that display call volumes by hour of the day and day of the week. Hour to hour, day to day and week to week, call volumes are predictable for any given switch and type of service. Routine examination of call volume can quickly detect missing information that has not been extracted, has been lost in the mail, or has not been brought into the editing process by operations.

Identifying All Billable Events

Mediation—with the help of manufacturer documentation and visibility of local switch tables (often called translations)—has to identify which calls were completed and, for billing purposes, discard those that are not required by billing. Depending on local business rules, the discards might include incomplete attempts such as ring-no-answer, busy called numbers, blocked trunks or routes (where the switch cannot find a path to complete the call in the network), voice mail deposits that are not to be charged to the customer and abandoned calls (incomplete dialed digits).

A useful report for this step is one that displays the actual count and percentage distribution of each category noted above. Just like call volume, these percentages are predictable. For example, if the switch in question typically records no more than 6 percent unbillable calls and one day that spikes to 10 percent or more, immediate investigation is warranted. Did new switch software or translation table entries fail to identify a category of completed calls? Is there a new error condition in the mediation editing step? Additional periodic reports might also include the number of outcollects (roamer records in mobile markets), voice mail activity, and call volumes by destination NPA or NPA-NNX. Again, volumes are typically predictable, and any sudden shift might be evidence of a network problem.

Reformatting or Normalizing CDRs

Depending on the service type, the switch may record data in an industry standard layout (typical for landline networks in the United States) or a format defined by the switch manufacturer. Either way, this step in mediation ensures that the billable records are formatted as required by the billing system. Given the high and ever increasing volume of CDRs, a major objective of mediation is to offload the rating engines as much as possible. Therefore in this step, mediation might perform certain translations—such as converting the dialed digits into the directory number of the called party, generating the city and state from the directory number, and other minor formatting tasks.

Guiding CDRs to Customer Accounts

Guiding the CDRs to particular accounts—a critical step—is performed by linking mediation to the customer or service database. Problems with this step are rare in well-controlled environments, but on occasion local or mobile telephone numbers may be in service, but not active in the billing system. This means the CDRs of a working telephone number cannot be associated with an account billing telephone number.

When this occurs, these calls have to be held in a recirculating error file, and the condition is reported. One useful report would be to have the mediation platform list all working numbers in the order that first displays, either those with the most number of unbilled minutes or those that have been in this error (or suspend) file the longest.

Determining Ability to Begin Rating

This is really the second step of guiding. Once the mediation system knows where to guide the CDR, it must ensure that it can identify the originating and terminating number locations, in order to determine whether a charge is to be applied to the call. For example, in an ILEC environment mediation may determine that the call was long distance and therefore to be billed by the LD company. In this case, a CDR would not be routed to the caller’s retail bill, but to wholesale (CABS) billing to bill the LD company for having handled the originating (or terminating) portion of the call.

The most common errors occur when a new terminating NPA-NNX or new country code has been activated somewhere, but has not been updated in the tariff tables of the billing system. As with unknown originating telephone numbers, these CDRs must be routed to the error file and reported.

Those are the main functions of mediation for voice services. Next month’s column will continue with a look at some of the new issues and challenges for this area as we enter the wireless Internet world.