Networks virtualization seemed, in 2015, to have beaten the usual pattern of over-expectation followed by a backlash prompted by lack of standards. ETSI’s NFV (Network Functions Virtualization) proved the center of a surprisingly rapid and well-supported process of establishing baseline specifications, and there was real hope that these specs would drive confidence and accelerated uptake. However, while there are some flagship operators deploying NFV-based systems, in general the second half of 2016 saw a cooling of enthusiasm, with early, small-scale trials failing to convert into larger commercial implementations. As always with this kind of pattern, there are many reasons, from changing budget priorities to uncertainty over use cases, but a key factor has been the danger of fragmentation and incompatibility.…