Complex Policy Implementation
Policy management in the UMTS, CDMA, and LTE networks is one of the fastest growing sectors of the market. As the demand for sophisticated policy implementations increases, Policy, Charging, and Rules Function (PCRF) testing becomes more difficult and more critical. Dynamic Policy Management based upon DPI, and the push to deliver voice over LTE (VoLTE), with the associated need for VoLTE testing, is accelerating this migration.
PCRF testing requires a test solution that has high capacity in terms of subscriber count and transactions per second, flexibility in terms of support for vendor-specific information, and coordination across interfaces. Developing Solutions has designed a solution to address the challenges of PCRF testing.
Unlike some test tools, dsTest provides stateful, standards-based applications that react appropriately to both expected and unexpected events without the need for scripting. Where dsTest surpasses all other tools is in its capacity, its performance, and the ease with which you can customize the scenarios and messages to achieve your PCRF testing goals.
You may be using Deep Packet Inspection (DPI) technology to provide functions such as packet classification, usage monitoring, value added services or intelligent traffic routing – applications that have been providing policy enforcement information to your PCRF. You need to verify that these applications still perform correctly with your latest PCC implementations.
With a single one rack unit server, dsTest can host hundreds of millions simulated subscribers. It can also scale to beyond 5,000 emulated nodes to create a virtual network that routes various traffic types towards the device under test.
dsTest is leading the performance testing market. Our interface applications such as Gx are completely stateful and capable of generating millions of transactions per second, thus elevating your PCRF testing to realistic network conditions.
dsTest utilizes a Subscriber Profile Repository (SPR) to host subscriber entries. Multiple emulated nodes can utilize the SPR to create complex signaling traffic across many interfaces. In addition to the subscriber information, each subscriber profile includes a SmartProfile, which allows you to define behavior and supplemental information.
The SmartEvents feature gives you the ability to extend the state machine of an interface application and to define the behavior of individual subscribers or groups of subscribers.
- Modify the behavior of an application
- Trigger client-initiated, server-initiated, or network-initiated procedures based on time or on the result of another procedure
- Coordinate the actions of multiple interface applications to simulate subscriber activity
Use the SmartAVP feature to insert, delete, or replace AVPs in Diameter messages. SmartAVP not only enables you to define proprietary signaling or to corrupt AVPs to facilitate negative testing, when used in conjunction with SmartEvents, you can specify exactly when your SmartAVPs are used.
Use Case: Voice over LTE
In the following example, dsTest emulates the PGW and P-CSCF to simulate VoLTE subscriber activity, initiating procedures with the PCRF over the Gx and Rx interfaces. In addition, dsTest hosts an emulated SPR that provides subscriber information to both the PCRF, over the Sh interface, and the emulated PGW and CSCF.
The shared subscriber database enables the PCRF to be provisioned with the same profiles that supply the emulated PGW and CSCF with subscriber identities, service definitions, custom AVPs, and the SmartEvents that define the four steps shown in the example message flow. Using a common repository keeps configured and dynamic subscriber information synchronized across all devices and applications.
1. Establish IP-CAN Session
Configure the PCEF emulator to initialize Gx IP-CAN sessions for some or all subscribers on startup at the rate you choose.
2. Activate Dedicated Bearer
Configure SmartEvents to generate AARs for the specified service at some time after the Gx session is established and then set a timer for the simulated call duration. The PCRF should respond and then generate an RAR requesting that the PCEF install a new rule for the subscriber, which would result in a dedicated bearer activation.
3. Terminate Dedicated Bearer
Configure SmartEvents to initiate a service deactivation when the call timer expires. Upon receipt of the STR the PCRF should respond to the CSCF and then notify the PCEF to delete the dedicated bearer by removing the rule previously installed.
4. Terminate IP-CAN Session
Configure SmartEvents to simulate a detach at a time of your choosing with a terminate event that generates an STR for the Gx session. The PCRF should delete the session and reply to the PCEF.