The ongoing extension of virtualization to the access networks of broadband and streaming services means that the concept now touches all parts of the content lifecycle. It also embraces different levels ranging from the underlying infrastructure to content processing and analytics, with an underlying migration towards large public clouds providing economies of scale. While bringing huge potential advantages, especially reduced TCO (Total Cost of Ownership) and faster deployment for new services, some of the challenges have tended to be overlooked, in particular greater complexity and increased exposure to cybersecurity threats, as well as increased storage requirements. Such considerations have motivated initiatives like the Joint Taskforce on Networked Media (or JT-NM), which in 2015 began defining a multi-layer reference architecture for…