VoLTE: It’s a question of QoE

According to the Global mobile Suppliers Association (GSA), LTE subscribers will reach 1.34 billion by 2018. Because more subscribers are going to migrate towards LTE for data, it is only a matter of time before Voice over LTE becomes inevitable.

The benefits of VoLTE over traditional cellular voice are compelling: better spectral efficiency, faster LTE data rates, and increased service to more users from the same cell sites. In terms of mobile devices, VoLTE offers faster call-setup times, high-definition (HD) voice, improved battery life, seamless handovers to legacy voice and VoWi-Fi, and simplified LTE architecture.

However, the key business challenge for commercial deployment of VoLTE hinges on the migration of the lucrative $500 billion per year voice business to LTE without compromising subscriber QoE. Operators are particularly reluctant due to the following factors:

• Expensive purchase, roll-out and integration costs of the IMS with legacy setups
• Seamless handovers (SRVCC) from LTE to legacy (2G/3G) glitches
• VoLTE roaming is still a challenge between operators and across geographies

What’s more, event when operators do decide to deploy VoLTE, they face several challenges during the entire rollout cycle regarding: IP multimedia subsystem (IMS) infrastructure, VoLTE coverage, audio quality, mobility, failures and end-user perception of the voice quality. Indeed, as end-user quality of experience (QoE) has a direct impact on the provisioned quality of service (QoS), it is crucial for operators to perform VoLTE performance monitoring during each phase of the deployment lifecycle to mitigate customer churn and increase the average revenue per user in the long run.

Is testing throughout the entire VoLTE deployment that important?

In one word: absolutely. A new VoLTE service deployment can be categorized into four phases: network rollout, field trials, commercial deployments and optimization.

Each phase has attributes that require unique validation solutions before transitioning to the next stage. From validations, including IMS and POLQA tests, to analyses to benchmarking to troubleshooting, comprehensive VoLTE assurance testing goes deep to optimize and improve the performance of the network.

Once operators dig deep into all the factors that can make or break VoLTE QoE, it may, at first, appear daunting. EXFO’s multi-pronged approach to VoLTE E2E Assurance provides a means for segmented and complete network-traffic analyses.

Combining analytics, mobile device solutions, verifier probes, analyzers and lab simulators, EXFO’s VoLTE assurance solutions provide operators assistance during each phase—including post-deployment.

To get the full story on VoLTE deployments and VoLTE testing—and how EXFO can help, check out our app notes.