NexTone Communications has announced that four of the seven GPRS Roaming Exchange (GRX) carriers used the NexTone IP Multimedia Exchange (IMX) platform to power their successful trials in the European and Asian interoperability tests.

The tests were conducted by the GSM Association (GSMA), a global trade association that exists to promote, protect, and enhance the interests of GSM mobile operators throughout the world.

The trials, conducted over the last six months, brought together mobile network operators, GRX carriers, and equipment suppliers to ensure that the next generation of multimedia services, based on the Session Initiation Protocol (SIP) and IP Multimedia Subsystems (IMS), will work smoothly and have compatibility across networks once these services are launched for customers. The tests are crucial for the many operators around the world that are planning to use IMS to handle multimedia services such as instant messaging, push-to-talk-over-cellular, video-sharing, and multiplayer-games in the future.