Integrating SAP Convergent Charging and Understanding its Architecture

The Core Server employs a modular architecture specifically designed for rating and charging, which comprises a network of server instances that function as business services. One key component is the dispatcher, a public instance responsible for managing and directing all incoming requests to the appropriate instances, making it the central hub of the Core Server.

The dispatcher has several capabilities, including:

• Facilitating communication with other instances via TCP/IP packets.
• Interfacing with the SAP CTS plugin through XML over HTTP.
• Receiving communications from client applications such as the Core Tool user interface, which may use XML over HTTP, SOAP over HTTP, or TCP/IP packets.
• Allowing discovery by other instances or client applications through UDP messages.

Dispatchers play a crucial role by processing and directing all incoming requests; thus, they maintain the only up-to-date version of the dynamic instance map. This map contains details of all active instances. Consequently, when other instances start up, they must initially connect to any available dispatcher. If a starting instance contacts a backup dispatcher, the request is immediately forwarded to the primary dispatcher which is tasked with maintaining and updating the dynamic instance map.

An updater is a public instance designed for provisioning operations that manage customer data. It can perform tasks such as:

• Interacting with client applications like the Core Tool user interface via an XML over HTTP channel.
• Communicating with the SAP CTS plugin through a SOAP over HTTP channel.
• Exchanging data with other instances using dispatchers.
• Linking with updater instances from other SAP Convergent Charging systems for the Catalog Transport feature using SOAP over HTTP.
• Working with external systems to manage individual user provisioning in SAP Convergent Charging through REST over HTTP.

A guider is a private instance used internally only and accessed by dispatchers to gather routing information for specific accesses. It cannot be accessed by client applications. A guider's main functions include:

• Gathering necessary access information at startup.
• Creating a service dictionary and a memory map with subscription and user identifiers.

A rater is another private instance focused on charging and recharging operations, which cannot be contacted by client applications. It processes all requests from the active dispatcher, and can be either:

• Stateful, affecting database content during charging.
• Stateless, performing rating services without altering databases.

Raters also handle sending and resending spending status reports and generating charged item data files after charging operations.

A bulkloader is an asynchronous private instance used to:

• Load charged item data files.
• Convert charged data into billable items as per predefined rules.
• Transfer the billable data to SAP Convergent Invoicing for billing purposes.

To improve the overall performance, bulkloaders operate periodically in a bulk execution mode.

The Core Tool is a desktop application fully developed in Java that serves as the graphical user interface for SAP Convergent Charging. It streamlines the management of numerous processes and operations available in SAP Convergent Charging, including:

• Implementation and customization of new services and pricing structures.
• Management of agreements (provider contracts, subscriptions).
• Dynamic pricing and launching promotions.
• Management of real-time customized offers and charging plans.
• Auditing of pricing and provisioning.

The Import/Export Connector is an optional add-on used to connect SAP Convergent Charging with external systems like back office and legacy applications. This component comes with a desktop application named CAT Tool, which enables interaction with the Import/Export Connector and access to its usage data records. Data transfers are outlined in scenarios that depict sequences of basic actions such as:

• Importing/exporting data from/to a file or data container.
• Modifying data.
• Executing a specified Java class.

This desktop application provides a set of components that facilitate the execution of data transfer operations.

The Diameter Server component functions as a message translator, converting credit-control messages from a Diameter client application into charging messages that the Core Server can process. It operates as an online mediation system.

Its credit-control features encompass the following:

• Real-time management and control of prepaid balances for services
• Alerting customers when their balance reaches specified thresholds
• Discontinuing a service session once a balance is exhausted
• Enhancing Credit-Control Answer (CCA) messages with attributes specific to particular network elements (Vendor-Specific Attributes or VSA)
• Implementing Diameter security measures such as TLS or IPSec
• Handling credit-control for multiple services in a single session

SAP Convergent Charging interacts with various databases used by its individual components. Each database stores data that is managed by particular processes and functions. These elements demand proper configuration and optimization for peak performance.

Supported database technologies by SAP Convergent Charging include:

• SAP HANA
• SAP ASE (formerly known as Sybase ASE)
• Oracle
• Microsoft SQL Server
• IBM DB2

The technical framework of SAP Convergent Charging integrates seamlessly into the broader SAP BRIM architecture. Next, we will look at a diagram depicting the technical components of SAP BRIM and outlining the specifics of their intercommunication.