ARM has joined the O-RAN Alliance, in an important, if belated, step forward for its own telecoms infrastructure ambitions, and for the goal of a truly multivendor mobile network platform from silicon to software. The O-RAN Alliance – originally spearheaded by AT&T and now under the custodianship of the Linux Foundation – is the most influential cross-industry initiative focused on specifications for an open, disaggregated, multivendor RAN. Together with Telecom Infra Project (TIP), a close partner, the Alliance aims to define common interfaces and platforms that will allow equipment and software from any vendor to interoperate. That, in turn, could lower barriers for smaller suppliers to enter the closely guarded, proprietary fortress of the big five RAN vendors, creating a…