Telecom Billing Usage Capturing - Telecom Billing

How to capture usage?

A customer will start using a Network as soon as they start using the products and services sold by an operator. Network element is a combination of software and hardware and is responsible for overall service control and managing events for any type of service.

What is an Event?

Event is a single billable incident of product usage and is captured electronically by a network. For example, when a mobile phone user makes a telephone call, an event will be generated which includes information about that phone call, such as call duration, time and the number that was called.

What is a CDR?

An event combined with its attributes is called Call Detail Record (CDR). A data collector in the network switch will capture the usage in the form of Call Detail Record (CDR)/Usage Detail Record (UDR). These raw CDRs/UDRs will be in turn converted by the mediation system into a format understandable by the Billing System.

Different network elements can control the services and produce various types of CDRs; for example, for GSM telephony

  • Voice calls will be captured by the MSC (Mobile Switching Centre).
  • SMS traffic will be captured by the SMSC.
  • Data traffic will be captured by the GGSN.
  • MMS traffic will be captured by the MMSC.
  • Roaming CDRs will be captured by roaming partner's switching element.

You can refer to our GSM tutorials for more information on GSM, MSC, SMS, SMSC, GGSN, MMS, MMSC.

Below diagram shows the Network elements capturing Usage data and sending Raw UDRs to the Mediation System and finally to the Billing System for rating and billing.


CDR Attributes

As mentioned above, a CDR maintains usage details along with various other useful information. Below are some of the important attributes of a CDR

  • Calling Party (A number).
  • Called Party (B number).
  • Call Start (date and time).
  • How long the call was (duration).
  • Call Type (Voice, SMS, Data etc).
  • A unique sequence number identifying the record.

Additionally, a CDR may also record other information such as

  • Identifier of the telephone exchange.
  • Result of the call (whether it was answered, busy, etc.).
  • Trunk or route used to connect the call.
  • Any fault condition encountered.
  • Indicators that note the usage of features such as call forwarding, three-way calling, etc.
  • Any facilities used during the call, such as call waiting or call diversion.
  • Several other attributes based on the requirement.

Correct recording of all necessary information in a UDR will depend on the logic of the switch vendor plus the switch specific table entries. If any of these is not able to record the data correctly, then the mediation system cannot recognize the completed calls and cannot pass them to the billing system.

CDR Processing

Mediation System will collect the CDRs from various network elements in various formats. Different network elements will generate CDRs in ASN.1 format and some network elements will have their own format of CDRs.

Mediation System can process all the CDRs and convert them into a format which is compatible to the downstream system, generally a Billing System. Mediation System will apply several rules on CDRs for processing them; for example, mediation system will mark the international calls based on the dialed number (B-Number), similarly mediation system will mark the on-net calls depending on A-Number and B-Number.

There can be a necessity of filtering out all the calls which have call duration less than 5 seconds. Best place to filter out such types of calls will be at Mediation System level. Similarly, if any critical information related to billing is required in the CDRs, then Mediation System helps in providing such information depending on some other attributes available within the CDRs.

Once the collected CDRs are processed, Mediation System will push all the CDRs to the Billing System by using FTP because Mediation and Billing systems will run on different machines.

What is Next?

As we have captured customer generated usage, we will discuss on how we can rate this captured usage so that due revenue can be collected from the end-user.

All rights reserved © 2018 Wisdom IT Services India Pvt. Ltd Protection Status

Telecom Billing Topics