2:30 PM -- China Mobile Communications Corp. and Vodafone Group plc (NYSE: VOD) will test Long Term Evolution (LTE) roaming and other interoperability scenarios in March next year. (See V'Fone, China Mobile Test LTE Roaming.)

They are the first operators to sign up for the MultiService Forum 's LTE and System Architecture Evolution (SAE) interoperability test that will start in March 2010.

The two have already worked together on LTE in a three-operator trial project with Verizon Wireless . And Vodafone says it continues to work with Verizon on field trials in the U.S. and in Europe. (See V'fone Germany to Test LTE for Rural Broadband, MWC 2009: Verizon Picks LTE Vendors, Huawei Joins Vodafone LTE Trial, Verizon, Vodafone Head for LTE, China Mobile Joins LTE Threesome, China Mobile Flexes LTE Muscle, and China Mobile Fast-Tracks TD-LTE .)

The MSF's interoperability event will be hosted by Vodafone's test and innovation center in Düsseldorf, Germany, and China Mobile facilities in Beijing.

A big focus of the tests will be the Evolved Packet Core (EPC), the core network for LTE radio access networks. Among the test scenarios are LTE access into the EPC, roaming, backward compatibility with 2G and 3G into the EPC, handover/relocation, and access into the IP Multimedia Subsystem (IMS) core network.

The tests are an important step for mobile carriers and show, too, how much there is yet to work out for the proto-4G technology.

— Michelle Donegan, European Editor, Unstrung