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McKinney, TX (October 4, 2012) – The protocols and interfaces for delivering VoLTE services are complex, and dsTest® simplifies the task of measuring performance.   Developing Solutions® continues to evolve the dsTest platform and looks forward to the opportunity to show network operators the many advanced features available to easily configure and quantify the performance of their network equipment, including VoLTE testing.

Testing Policy Management

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With dsTest, users can simulate VoLTE call flows by setting a probability assignment for the number of subscribers that will place voice calls, and a load profile can be created that produces the desired volume of simulated voice traffic transactions, thereby triggering the appropriate procedures that would establish dedicated bearers for the traffic.

In one 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 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.

You can shape the aggregate load profile while randomizing the actions taken by a particular subscriber, resulting in a more realistic simulation of subscriber activities.

VoLTE call flow with DRA

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In more complex testing scenarios, this type of load profile would be useful in testing all nodes involved with the VoLTE call flow, including the PCRF, HSS, OCS, OFCS, MME, PGW, PCEF, and CTF.  Along with VoLTE call flow testing, the inclusion of a DRA can test the Diameter signaling routing in the simulation.

Developing Solutions showcased a VoLTE environment at GSMA’s Mobile World Congress 2012. This environment simulated the wide range of Diameter transactions and interfaces required to support VoLTE calls. The exhibit included the verification of routing of dynamic policy and charging transactions between many core EPC elements.

The features of dsTest allow the user to easily create complex testing scenarios spanning multiple application interfaces.  Our dsClient™ GUI can be used to configure the test scenarios, producing fully functional and validated XML configuration files ready for dsTest.  The GUI’s drag-n-drop wizard allows users to draw a state machine diagram on a canvas, with the GUI automatically building the corresponding XML configuration.

Read more about our Advanced Diameter Testing Features.
Read more about our dsClient GUI.

About dsTest

dsTest focuses on the Subscriber Management, PCC, and SMS interfaces in the mobile packet core network. Our Interface applications can validate the stability and performance of network elements, and our HSS, PCRF, and Charging server emulators can be passive or active participants in the lab, and enable lab network administrators to quickly and easily configure subscriber and policy settings.

dsTest scales to support thousands of network connections, tens of millions of subscribers, and hundreds of thousands of transactions per second from a single server.

To learn more about Developing Solutions® core network emulation and test solutions, refer to our product page or contact Developing Solutions, Inc. at

About Developing Solutions, Inc.

Developing Solutions, Inc. is a test equipment software development firm founded in 2002 with extensive experience in the Telecom and Datacom industries, including both NEM and test equipment manufacturers. Developing Solutions is located in the DFW Metroplex.