The holy grail of true multivendor networks is an important attraction of virtualization for many operators. But for most, the challenges of moving to a virtualized platform are daunting enough, without getting multiple suppliers involved, so early trials are generally being run by a single vendor. Except in Japan, where – as so often – NTT Docomo is taking the lead in showing the others what can be done. For operators for which ‘multivendor’ often meant no more than splitting a RAN roll-out into two separate regions, with one supplier apiece, the idea of being able to mix and match their partners, and swap kit in and out relatively easily, is appealing – but, of course, easier said than done.…