If we define Open RAN in its widest sense, as a multivendor network based on open interfaces, the fastest progress has been made not in Europe, but in the USA and south-east Asia. Rakuten Mobile in Japan, and Dish Network in the USA, are of course the first operators to deploy a virtualized Open RAN at scale. AT&T and China Mobile contributed much of the original sourcecode for O-RAN, and these operators, as well as Verizon, NTT Docomo and SK Telecom – among others – have defined open RAN specifications and pledged roll-outs from this year onwards. However, in most cases these open networks are highly customized and do not necessarily use standard O-RAN specs (even in AT&T’s case). They…