Japanese cloud networking pioneer Rakuten says it's time traditional telcos took the plunge into virtualization.For brownfield operators with legacy networks, it had become "a matter of survivability," said CTO Tareq Amin."The fabric of everything that we do in society has moved to software, and software has moved to the cloud," he told the company's annual customer event Tuesday.He said telcos should start on small projects to begin the shift to cloud-based architecture."You could start with smaller areas. Get out of the lab. I think we have done enough lab testing.""This technology works. It works really well," said Amin, who has just been named CEO of Rakuten's new technology unit Symphony."It's critical now to start having a bigger objective and vision; you don't need to disrupt your entire network."Opening upMichael Martin, director of mobile radio for new German operator 1+1, Symphony's first major customer, said telco leaders needed to be bold."The whole industry needs to be bold, needs to allow [itself] to go the next step in the evolution, which is clearly open RAN," he said.In his previous role as a telco exec he had hesitated to embrace the cloud for fear it might threaten network performance."But with my knowledge of today I would give the advice to my former self to be bold, to look into it, to go into the first live pilots with live customers and gain experience. One thing is clear: for networks that don't change; there will be a forced change in the future. I am happy to be on the frontrunner side instead of the following side," he said.Looking cloudyRakuten boss Mickey Mikitani likened Symphony to Amazon's AWS. Just as the US e-commerce giant had turned its IT backend into a cloud business, Rakuten aimed to turn its virtual radio network and cloud architecture into a global cloud platform business to sell to other operators.It would be a 15 trillion yen ($132 billion) market by 2025, Mikitani said. "We can provide all of the services – the only company that can do that."He said Symphony was one of Rakuten Mobile's three pillars, along with the mobile operator business and the Rakuten Group "ecosystem" that comprised businesses in multiple verticals and a 100 million customer base.Rakuten, which started its MNO service in June last year, now has 5 million customers.The network covered 93.3% of Japan's population at the end of September and would reach 96% by Q2 next year, Mikitani said.