Long-time virtualization advocate Japan’s NTT Docomo said this month that it has finally achieved complete virtualization of its core network. While its compatriot Rakuten Mobile has long been operating a virtualized, or cloud-native, 5G core, Docomo approached the task with a legacy mobile network of varying generations – a harder task. Docomo’s efforts in this space have led to questions about the broader adoption of public cloud for hosting core network software, but there remains a conservatism in the sector. Docomo’s own decision to operate a hybrid core cloud system that uses public cloud in on-premises compute resources indicates the limited appetite for public cloud platforms. Docomo said that Cisco, Dell Technologies, NEC, Ericsson Japan, and other partner companies provided…