With the wireless industry moving toward a unified IP network carrying both voice and data traffic, policy and charging rules function (PCRF) will be taking on an increasingly important role in managing the service provider’s network resources and monetization of service usage. And, with the planned adoption of Voice over LTE (VoLTE), PCRF will be playing an increasingly vital role in the network.
A key component of building a fast and reliable wireless network includes extensive testing of the network elements (NEs), in this case PCRF in the test labs before deployment. In test labs, PCRF is normally tested with other real NEs, such as PDN GW. Such a test setup does not fully exercise the functionality, performance or capacity of PCRF, because PCRF not only communicates with single PDN GW, but multiple PDN GWs. PCRF also communicates with policy control enforcement function (PCEF), such as deep-packet-inspection (DPI), online-charging-system (OCS), and offline-charging-system (OFCS) functions, as well as other PCRFs (visited), call session control function (CSCF), serving gateway (SGW), gateway GPRS support node (GGSN), traffic detection function (TDF) and more.
As the demand for sophisticated policy and charging implementation increases, PCRF testing becomes more difficult and more critical. As such, it is important to select full-featured test equipment with enhanced test coverage to isolate and surround test PCRF. This will ensure the service provider is obtaining the performance, capacity, features and stability needed for the equipment deployed in the network.
EXFO’s dsTestTM Diameter test product powered by Developing Solutions® is a complementary solution to the EXFO QualityAssurer simulator product, and helps to isolate and surround test PCRF. DsTestTM supports the complete PCRF feature set defined by the 3GPP specification, from installation, modification and removal of policy and charging control (PCC) rules to binding and quality of service (QoS) parameter mapping, requesting and reporting usage, and failover and restoration procedures.
EXFO’s Diameter simulator test solution delivers the best, scalable high capacity and high performance in the industry leveraging commercial off-the-shelf (COTS) hardware multicore servers, coupled with unmatched flexibility and user-friendliness. Here’s a quick summary of the key features offered by the EXFO test solution for PCRF network element testing:
- Ability to reproduce events
Enables the operator to quickly reproduce a network event or sequence of events, and eliminates countless hours of reconfiguration.
- Results verification
Verifies that an action on one application interface will result in an appropriate action on another application interface.
- Ability to push a PCRF to its maximum capacity and performance
Today’s PCRF devices need to have the capacity to handle tens of millions of simultaneous active subscribers while processing tens of thousands of transactions per second, and should be able to achieve those capacities with a single piece of hardware, rather than using multiple servers. EXFO offers a single piece of hardware, and also enables hosting of the entire subscriber pool, rather than dividing subscribers into groups that must be separately configured and emulated across multiple nodes.
- Ability to coordinate events across application interfaces
To adequately test PCRF, test engineers need more control over testing than simply generating messages at some predetermined rate into each application interface, and must be able to synchronize messages on multiple application interfaces.
- Ability to capture and store detailed test results
A fundamental requirement of any test equipment is its ability to store results for off-line processing and analysis. Maintaining historical information from previous tests enables you to establish a baseline for how well the PCRF performs, which is useful for ensuring that future releases of the PCRF do not significantly degrade its performance or capacity. Also, the statistics captured by the test solution provide sufficient detail to allow for correlation of information, and can be synchronized so that they can be correlated from one application interface to another for a given interval of time.
- Ability to create both fixed and realistic interaction
Many network issues are discovered by randomizing the behavior of the tests, so the ability to set up tests that don’t always generate the same sequence of events is an important component of any test plan. As such, the PCRF test solution allows for the creation of complex load profiles for accurate reproduction of live network scenarios.
- Ability to inject errors
Offers the capability required to inject a variety of error scenarios that would be seen in the live network. In addition, it enables you to inject error messages and sequences into the PCRF, and to subsequently verify whether it can detect and recover from the error scenarios.
- A turnkey, yet flexible solution
Provides capability needed to handle the applications that you are interested in testing, and to take stock of the message contents and sequences used in each of those applications. For the needs of functional testing, it provides the flexibility to customize virtually any aspect of the application protocol (including the ability to perform negative testing), and has the capacity to share subscriber data across application interfaces.
- Expansion capability
Offers the capabilities you require to meet your needs as your circumstances change, with minimal dependency on custom hardware so that you can keep up with Moore’s Law over the long term.
For more about EXFO’s purpose-built solutions for large-scale emulation and testing of elements, networks and services such as VoIP, IMS, LTE, VoLTE and WebRTC, check out our Network Simulation and Load Testing web page, which details all of our simulator test solutions, including LTE, EPC and IMS networks and services such as VoLTE and WebRTC.