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McKinney, TX (April 21, 2015) – Network Testing Solutions: VoLTE Testing With dsTest.

The protocols and interfaces for delivering VoLTE services are complex, but dsTest simplifies the tasks of compliance and measuring performance of network configurations.  Developing Solutions continues to evolve the dsTest platform with advanced features available to easily configure, test, and quantify the performance of their network equipment, including VoLTE testing.

With dsTest, users can simulate VoLTE call flows by setting a probability assignment for the number of subscribers that will place voice calls, and load profiles can be created that produce 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 a PCRF over the Gx and Rx interfaces.  In VoLTE Testing, Testing Policy Management, dsTest, Developing Solutionsaddition, 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 profiles while randomizing the actions taken by a particular subscriber, resulting in a more realistic simulation of subscriber activities.

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.VoLTE Testing, dsTest, Testing Policy Management, Developing Solutions

Developing Solutions has showcased a VoLTE environment at GSMA’s Mobile World Congress and other industry forums.  This environment simulates the wide range of Diameter transactions and interfaces required to support VoLTE calls, including 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.

About dsTest

Developing Solutions’ growing collection of protocol applications and EPC testing tools gives dsTest the ability to identify problems and potential bottlenecks in the lab before they show up in the network.

dsTest runs on several distributions of Linux and is designed to take advantage of the latest processor and virtualization technology available with COTS hardware in order to provide high performance and capacity, and assists carriers and vendors in their drive toward network function virtualization (NFV) and software defined networks (SDN).    Wireless Service Providers and Network Equipment Manufacturers rely on dsTest to test performance, compliance, and reliability of their network devices and architectures.  dsTest is accompanied by the dsClient graphic user interface (GUI), which allows easy configuration and control of the tool, and provides live operational measurements monitoring in chart or tabular form.

dsTest further simplifies the process of testing the signaling core with multiple advanced testing features, such as SmartEvents, Diameter Dictionary validation, and SmartAVP customized messages.

General References

Diameter Result Codes
Diameter Dictionary
Specification Map

Use Cases

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 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 helps carriers and equipment manufacturers avoid costly downtime by easily scaling an environment to simulate hundreds of millions of subscribers to test capacity, compliance, scalability and redundancy.  The company is located in the DFW Metroplex.