As an OCS (Online Charging System), PortaBilling can be integrated with 2.5/3G and 4G mobile networks. In 2.5 and 3G networks, the CAMEL protocol is the de-facto standard for real-time charging.
In this case, PortaBilling can interoperate with mobile operator networks via the third-party CAMEL gateway.
In this configuration, the third-party CAMEL gateway is deployed within a service provider’s network and acts as a mediation component between PortaBilling and a mobile operator’s network, converting the CAMEL protocol to the Diameter protocol and vice versa.
This allows PortaBilling to communicate with the MSC (Mobile Switching Center) – a switching node that routes calls and messages to and from other telecommunication networks, including PSTN, ISDN, and other mobile operators’ networks – for real-time calls and SMS authorization and rating.
When a customer makes a call, MSC performs the call authorization in PortaBilling to verify that the customer has sufficient balance and is allowed to call that destination. Since MSC uses the CAMEL protocol, its call authorization request is sent via the third-party CAMEL gateway, where it is converted to Diameter Ro and then delivered to PortaBilling. PortaBilling locks in the funds to cover the initial period of the call and sends a confirmation message to MSC. This message also passes via the third-party CAMEL gateway where it is converted to CAMEL and then delivered to MSC.
When the period is over, MSC sends a request to lock in the funds for the subsequent period, etc. When the call is over, MCS sends a Credit Control Request - Terminate (CCR-Terminate) message to PortaBilling to report the end of the call. PortaBilling produces a CDR record for this call. In the message exchange between MCS and PortaBilling all the protocol conversion – from CAMEL to Diameter and from Diameter to CAMEL – is done using the third-party CAMEL gateway.
A similar procedure is followed when a customer sends an SMS.
This kind of integration allows service providers interested in entering the mobile market to integrate with mobile operator’s networks that use the CAMEL (Phase 1, 2, and 3) protocol to communicate with a billing system for real-time call authorization and rating.