SANTA CLARA, Calif. — In an effort to set an industry standard for mobile security, ARM Holdings has asked a handful of mobile chip makers to help define the next-generation applications programming interface for its TrustZone extensions to the ARM core.

Companies including Broadcom and Motorola welcomed the effort, although others are taking a wait-and-see approach in a sector that is undergoing increasing fragmentation.

"We need more commonality across [cellular platforms], and to make that happen, ARM launched today a user group for the evolution of their TrustZone API," Dominique Bolignano, chief executive of Trusted Logic, an ARM partner speaking at a panel on mobile security at the third annual ARM Developers Conference here on Wednesday (Oct. 4).

"This is all about making security easier to implement. It's all about interoperability of components . . . but it's still early days for a standard API," said another panelist, Richard Phelan, product manager for ARM's TrustZone,. "We will be working on this over the next two years," he added.

"I like the ARM API," said Andrew Bennett, an engineering manager developing the Linux/Java cellphone platform for Motorola Inc. "We ship multiple handsets with multiple chip sets, so if there is a standard it means we can lower our costs of development and get products out faster," he said.

Motorola is already locked down on its 2007 handset products, but the new API could shape 2008 and 2009 products now in development, he added.

The ARM initiative faces competition from other groups trying to establish specifications for mobile security. The PC-oriented Trusted Computing Group recently released a handset security standard using a version of its Trusted Platform Module (TPM) hardware. The Open Mobile Alliance (OMA) has done significant work on mobile security, and the Java Community Process has developed mobile security standards.