Voice and SMS services are the primary revenue sources for mobile operators, contributing close to 80% of the overall revenue. Over-the-top (OTT) voice and video service providers are a significant threat to steal market share from mobile operators. Operators may be reluctant to commit large amounts of capital to LTE deployments without having confidence that they will be able to provide customers with voice quality and reliability equivalent to that of existing 2G and 3G networks. Support of toll grade, operator supported voices services over LTE’s all IP infrastructure presents a substantial technological challenge. Ixia has introduced a new test application to its IxLoad solution to measure voice quality end-to-end, from the cell tower through the core network. Operators can easily compare and contrast the voice quality of over-the-top (OTT) service to operator-provided voice services. Using best-in-class industry algorithms, operators can measure the mean opinion score (MOS) of voice quality before going live. Additionally, Ixia’s new application tests the functionality, scalability, and resiliency of LTE infrastructure components and new IMS networks that support VoLTE-based services.