GAINING CONTROL OF DATA ROAMING SPENDING

using nobill® Roaming data contRol to oFFER a suPERioR sERVicE

WhITE PAPER

2 June 2009

IntroductionWith the use of mobile roaming data services on the rise, it is becoming increasingly important for mobile operators to provide their customers with tools to control their roaming data spending. Apart from being a valuable service for subscribers, new regulatory requirements in the European market demand that operators offer a basic roaming data control from March 2010.

Operating in real time and with extensive support for subscriber interaction, Nobill Roaming Data Control from Symsoft presents an excellent option for operators seeking to provide a better roaming data service to their subscribers while complying to regulatory requirements.

This white paper will introduce operators to different methods of implementing roaming data control solutions, the requirements of the new European roaming regulation and will also highlight the capabilities of the Nobill Roaming Data Control solution that let operators differentiate their service.

BackgroundThe uptake of mobile IP services has grown tremendously in the last few years. Thanks to improved network coverage and increased speed, subscribers can today access IP based services on their phones and connect their laptops wherever they are. This also extends to subscribers roaming outside of their home network. However, it is today difficult for subscribers to estimate the cost of their service usage as mobile IP services are generally billed by traffic volume, which can be difficult to gauge. Subscribers that pay a fixed price per month in the home network may even be unaware that there is a cost. Lack of immediate accessible information on the cost for IP service use in roaming networks has led to repeated cases of bill shock, where subscribers realize the cost of their service use only after receiving their phone bill at the end of the month.

To set common standards for roaming data cost transparency across Europe, the European Parliament has mandated all operators in the EU to provide a service by March 2010, where the subscriber can set his/her maximum financial limit for a specified period of use (EC 717/2007 article 6a). If the limit is reached, the roaming data services shall be blocked. Below is an extract from EC 717/2007 article 6a:

“[By] 1 March 2010, each home provider shall give to all their roaming customers the opportunity to opt deliberately and free of charge for a facility which provides information on the accumulated consumption expressed in volume or in the currency in which the roaming customer is billed for[…] When this financial or volume limit would otherwise be exceeded, a notification shall be sent to the roaming customer’s mobile telephone or other device. This notification shall indicate the procedure to be followed if the customer wishes to continue provision of those services[…] If the roaming customer does not respond as prompted in the notification received, the home provider shall immediately cease to provide and charge the roaming customer for regulated data roaming services”.

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In short, the regulatory requirements demand that operators provide the following functionality to their subscribers:

• Ratenotificationswhenroamingintoanothernetwork

• Notificationsandblockingofservicewhenpassingcertainconsumptionthresholds

Many operators have already implemented rate notifications using their existing solutions for welcome SMS messages, but specific consumption thresholds for roaming mobile data is generally not provided to customers today.

Most operators are therefore required to implement basic new functionality to provide a certain level of cost transparency to their subscribers. However, this also presents an opportunity for differentiation. By offering better support for customizable cost control, operators can attract subscribers that regularly use data services when roaming and encourage further usage. To meet the regulatory requirements and to provide better cost control to subscribers, it is important to understand the demands put on the network and how these demands can be met.

Regulatory implications for mobile networksTo provide the cost control required by the regulation, operators need to monitor spending continuously in real time. However, systems managing postpaid subscribers normally handle rating and charging as a batch job at the time of billing, usually once a month. While many operators have solutions in place to give a limited support for spending limits, these systems often rely on hot billing approaches where there is a significant delay between service use and control mechanism.

These existing charging procedures for roaming traffic are clearly not fast enough for regulatory compliance or prevention of revenue leakage and bill-shocks. Consider the simple example with a rather modest 1 Mbit/sec connection. A hot billing system with 1 minute delay will risk the usage of 60 Mbit = 7.5MB before the service is blocked. A typical tariff of 8 Euro/MB will in this case mean a 60 Euro charge of either unpleasant surprise for the subscriber or revenue leakage for the operator. It would also be a clear violation of the regulation. Furthermore, a hot billing solution will not be able to communicate notification messages to subscribers in real time.

Consequently, the new requirements from the EU demand full real-time management of all subscribers capable of roaming including functions such as rating, usage control and end-user communication.

WhITE PAPER

4 June 2009

Typical Network ArchitectureTo fully understand the implications of real-time cost control, it is important to understand the underlying traffic and charging flow in the network.

When a subscriber connects to a foreign network, he/she is connected to an SGSN in the visited network. The SGSN routes traffic to/from the subscriber to the GGSN in the home operator network.The GGSN in turn relays traffic to the internet.

The charging process is normally managed by the GGSN with interfaces to either an on-line charging system for prepaid services or to an off-line postpaid billing system. According to the 3GPP baseline architecture for GPRS charging and billing management, the interface used by the GGSN is either an on-line interface known as Gy or an off-line CDR-based interface known as Ga (see illustration below).

InternetSGSN

PrepaidChargingSystem

GGSNGiGn

PostpaidBilling

System

Gy Ga

Home network

Visited network

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Limitations of the current architectureThe current off-line billing architecture deployed at a majority of European operators are not designed for real-time, meaning that it cannot comply with the regulatory requirements using existing systems. The technical deficiency often lies in the limitations that the postpaid billing system does not support real-time protocols such as Diameter, or that the GGSN is unable to handle real-time charging altogether. Instead these systems often rate and charge based on CDRs, provided in batch by the GGSN over the Ga interface.

While it might be possible to replicate all postpaid subscriber data in the existing on-line charging system, this would likely put undue stress on this system and it would still require that the charging system receives real-time information from the GGSN. Furthermore, many prepaid systems lack the needed functionality. In most cases, a dedicated stand-alone solution is the preferred way to conform to the regulatory requirements.

Using Nobill Roaming Data ControlNobill Roaming Data Control is a solution providing real-time cost control for subscribers using roaming data services. Building on the flexible Nobill platform, it provides functionality above and beyond what is initially needed for regulatory compliance so to promote usage of mobile data services. Nobill Roaming Data Control has flexible consumption caps, letting operators define more usage caps than those mandated in EC 717/2007. Furthermore, customers can change their consumption cap and customize their notification preferences using a number of different channels such as web interfaces, customer care and USSD. With USSD, instant changes can be made without customer care interaction. Notifications of current consumption can be dispatched using USSD, SMS and e-mail messages. It is even possible to send notifications to several mobile phones in case a subscriber is unable to receive messages on the device using mobile data services.

Roaming Data Control is based on the Nobill Platform which provides the architectural foundation for flexibility, scalability, and high availability. The system is written in Java and takes advantage of modern software technology, giving a system that is easy to modify, easy to partition and which is cost efficient.

At the core of the product, there is a subscriber database. This database manages all roaming subscribers and their roaming profiles including individual limit and subscriber specific information such as e-mail addresses and mobile numbers where to send notifications. Usage counters are connected with each subscriber account. These counters keep track of the current usage in real time, meaning that all usage will be updated instantaneously when subscribers access any roaming data service. As soon as a counter reaches a predefined threshold, the appropriate action will be performed. This action may include blocking of roaming data traffic and/or sending a notification to the subscriber. The messaging part is handled by the Message Generating Module, which will interface messaging systems in the operator environment, such as SMSCs and/or mail servers.

WhITE PAPER

6 June 2009

Depending on the chosen solution, the system will interface the traffic nodes either over a real time signaling protocol such as Diameter, or by monitoring the actual IP flow. In the case of a signaling based solution the Diameter server terminates the incoming Diameter requests from the network. In the case of a solution where the actual IP flow is handled, the IP Traffic module will terminate and analyze the traffic.

IP Traffic Module

Message Generating

Module

Usage Counters

SubscriberDatabase

Rating Engine

Diameter Server

Nobill Platform

Nobill Roaming Data Control

Independent of which solution is used, the world class Nobill Rating Engine will make sure that the current roaming tariffs are in line with the tariffs in the existing billing and charging systems, so that the limits can reflect the current roaming price plans in a proper way.

There are no modifications necessary in the existing postpaid rating flow, as the billing system will continue receiving CDRs from the GGSN for traffic use. It is however possible to configure the Roaming Data Control (RDC) to send enhanced CDRs if required. When the RDC has detected a limit, the blocking can be effectuated in the network either by RDC refusing further quota requests from the GGSN or via a RADIUS request to the GGSN to tear down the PDP context. The solution supports subscriber limits set in either volume or monetary terms. As mentioned above, Nobill Roaming Data Control adapts to the capabilities of the operator’s GGSN. If the GGSN supports on-line charging, the solution will receive information over the Gy interface, or over any other propriety interface. If this is not possible, it will instead monitor IP packets to gather information on the traffic load and charges for individual subscribers.

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Nobill Roaming Data Control integrated on a real-time rating interfaceIn the case where the existing GGSN has real-time capabilities, the Nobill Roaming Data Control by Symsoft may act as a real-time enabler for the off-line billing and charging systems. By using the real-time capabilities of the GGSN, all subscribers, both prepaid and postpaid, can be served by the on-line Gy interface or corresponding propriety interface. The Nobill Roaming Data Control will keep track of roaming data usage in real time for each subscriber. If an individual roaming limit is reached the system will block traffic according to EC 717/2007, send an SMS, USSD or e-mail to the subscriber informing about the block and offer the possibility to increase the limit.

InternetSGSN

PrepaidChargingSystem

GGSNGiGn

PostpaidBilling

System

Gy

Ga

Home network

Visited network

Nobill Roaming Data Control

Gy

WhITE PAPER

8 June 2009

Nobill Roaming Data Control integrated on the Gi interfaceIn the cases where the GGSN lacks real-time capabilities the Nobill Roaming Data Control will instead rely on intercepting the actual IP traffic. In this implementation, the product is situated on the Gi interface of the GGSN. In this scenario the RDC will monitor the roaming traffic and keep track of usage for each subscriber and block when the usage limit has been reached.

InternetSGSN

PrepaidChargingSystem

GGSNGiGn

PostpaidBilling

System

Ga Ga

Home network

Visited network

Nobill Roaming

Data Control

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Conclusion The requirements outlined in EC 717/2007 cannot be met without real-time roaming data control capabilities where monitoring is part of the service delivery. Even with minimal delays, off-line CDR-based charging solutions can not react with the speed required to fulfill regulatory requirements.

Regardless of the capability for real-time charging in the existing infrastructure, it is possible to implement solutions that assures regulatory compliance and protects operators against customer dissatisfaction and operator revenue loss.

Furthermore, by implementing a solution that allows subscribers to manage their individual usage limits and notification settings, operators have an opportunity to differentiate from the competition. This will make their services more to compelling subscribers that are interested in using data services while roaming.

With Nobill Roaming Data Control, operators can fulfill all these regulatory requirements while offering their subscribers a superior service. Building on Symsoft’s long experience of integration in mobile networks and using a modular architecture, the Nobill Roaming Data Control solution can be integrated in any network regardless of the existing network architecture.

Symsoft AB Kista Science Tower (Head Office)PO Box 1219, SE-164 28 Kista, SwedenPhone: +46 8 566 166 00Fax: +46 8 566 166 01www.symsoft.com

Symsoft develops leading real-time telecom solutions for mobile and convergent operators within the areas of charging, messaging, call completion and mobile data. Renowned for its ability to deliver, Symsoft enables operators in an increasingly competitive world to improve both attractiveness and ARPU. All application solutions are based on the carrier grade Nobill platform which exceeds operators’ requirements for business critical functions due to its modular platform architecture and innovative technology. Symsoft’s customers include leading telecom operators such as Millicom, Polkomtel, Qtel, Saudi Telecom, Telefonica, Telenor and TeliaSonera. Founded in 1989 and headquartered in Stockholm, Sweden, Symsoft has local presence in four regions and operational systems in more than 30 countries. © 2009, Symsoft AB. All rights reserved.