Rakuten Mobile’s 4G and 5G commercial networks have seen deployment of a power saving solution from Nokia designed for optical transmission.

The solution is made for optical transmission equipment utilizing dense wavelength division multiplexing (DWDM), which enables dozens or even hundreds of separate light signals at different wavelengths through a single fiber strand, aided by programmable channel spacing.

Nokia’s offering reportedly enabled remote control of idle expansion modules within optical transmission systems deployed across Rakuten Mobile’s edge data centers in Japan. By streamlining the power consumption of modules such as optical transmission devices and routers, Rakuten said the electricity usage of Nokia’s optical transmission equipment in these facilities will reduce by roughly 24% compared with conventional levels. This has the potential to significantly lower utility costs and CO₂ emissions, alongside network operational expenses via remote execution.

"AI compute is increasing power consumption [in data centers]. Rakuten’s use of Nokia’s optical power saving solution is important for countering those energy costs," Daryl Schoolar, analyst and director at Recon Analytics, told SDxCentral. "Rakuten has publicly committed to greater energy sustainability and the Nokia deal is just one step towards achieving that goal."

The Rakuten and Nokia partnership

The deployment – claimed to be a first for the Asia-Pacific region – represents the latest deal between Nokia and Rakuten. This summer, Rakuten Mobile chose Nokia to deliver cloud-native network functions (CNFs) for its 5G standalone (5G SA) mobile network deployment in Japan. Nokia’s CNFs were reported to cover authentication, user data management, signaling, analytics, and IMS voice, with their lifecycle operations automated via Nokia management tools, tailored for multicloud, multivendor environments.

Nokia also supplied radio access network (RAN) gear and mobile transport solutions during Rakuten’s pre-launch phase in 2019. Since then the two companies have worked together on 5G deployment and cloud-native integration, with Rakuten leveraging Nokia’s 5G SA-ready AirGile cloud-native platform.

Rakuten last year also began testing Nokia’s wavelength routing tech for long haul and metro optical networks to create the photonic mesh mobile backhaul network necessary for its 5G-Advanced service to become reality.

With Nokia’s partnership on its 4G and 5G commercial networks, Rakuten is hoping for improved network flexibility and efficiency across its infrastructure, from the network edge, through metro and long-haul transport, to subsea connections.