In telecommunications rating is the activity of determining the cost of a particular call. The rating process involves converting call-related data into a monetary-equivalent value.
Call-related data is generated at various points in the network or measurements may be taken by third party equipment such as network probes. Generally this data is something quantifiable and specific. The usage data so gathered is then either packaged by the equipment or it may be sent to a charging gateway.
Rating systems typically use some or all of the following types of data about a call:
Generally individual calls are rated and then the rated amounts are sent to a billing system to provide a bill to the subscriber. Often the rating system will be a module of a larger "Billing System" architecture.
A rating system must be adapted to the constantly changing pricing policies, which have the strategic goal of stimulating demand.
EDR stands for Event Data Record. EDR records are used for systems that charge more than calls - content. eg. buying ring tones). The generated CDR/EDR may not be in a form suitable for the particular rating system. In this case a piece of software, known as the mediation system, may be required to render the data into a form useful by the rating system. The mediation system is also useful for gathering data from various sources to aggregate into one record.
As the telecommunications market comes under increasing pressure from new technologies (for example WiMAX), the leading differentiating factors between competing operators is often the innovation in new product offerings, and time to market. This leads to a natural tension between the capabilities that are offered by:
In real life situations, even the most configurable systems generally have an implementation phase, in which new capabilities are created using programming methods, and a configuration phase, in which the new capabilities are configured and offered to the mass market.
As competition increased in the telecommunications space, rating is getting increasingly complex. Some rating scenarios use multiple measurements.
Example: Rating for a video download may involve measuring the number of minutes, the amount of data, the quality of data transfer as identified by the service level agreement (SLA) and the usage (copyright) cost of the video.
Complex rating could also involve non-network related parameters. Some of the rating data may come from the customer care or billing sub-systems.
Example: When usage above a certain amount is triggered in the billing sub-system the rating engine may assign a lower rate for the user. This is also known as an adjusting rate and can be complex to model in certain system.
Complex rating behaviour could be due to particular real or virtual behaviour
Example: Subscribers who play an affiliated on line game may trade in-game currency or equipment or incentive tokens for discounted calls to other players of the game.
Among the issues of rating, is taking account of Daylight Savings Time time offsets.
Modern rating engines may also be currency neutral. Certain multi-national telecommunication providers provide the ability for subscribers settlement in multiple currencies. In this scenario the rating engine generates a currency neutral billing record. It is the billing engine which is assigned with converting the virtual currency into an actualized cost.
In some scenarios it may be necessary to re-rate calls but not all rating engines are capable of this. There is a philosophical argument as to the usefulness of re-rating, with no clear correct answer: