Quantifying the real ‘on-net’ Rakuten network experience

In our just published Japan Mobile Network Experience Report, Rakuten won the Upload Speed Experience Award. This is an impressive achievement for a new network and especially for one which relies on a national roaming partner, KDDI, to offer its users service in areas where Rakuten’s own network is not yet available.

Rakuten launched its 4G mobile network on April 8, 2020. Since then it has scaled its business with over a million applications for Rakuten’s mobile service within three months of the launch. Adding large numbers of new users places greater demands on the innovative new network design the company has been building. Now, in the month immediately before Rakuten’s 5G launch on September 30, we examine how well Rakuten’s approach is meeting its mobile users’ needs at scale and how the experience differs when using Rakuten’s own network and its roaming partner.  

In Opensignal’s mobile analytics we see a much better mobile experience when Rakuten users are connected to its own radio network. The average Upload Speed Experience is two and a half times faster on-net than when roaming. The on-net average upload speed of 18.9 Mbps is also more than twice as fast as the experience offered by the established mobile operators au, Docomo and SoftBank. 

Similarly, Rakuten users’ average Download Speed Experience is 29.0 Mbps on-net versus just 13.6 Mbps when roaming. In other words, the experience is over twice as fast when using Rakuten’s radio network. This means that the quicker that Rakuten is able to extend the reach of its network the more users will spend more time enjoying this faster experience and their overall experience should improve. 

In its first quarter results, Rakuten reported that it is ahead of plan with its network roll-out with 4,738 base stations on air against a commitment to MIC of 3,432. At the end of June, Rakuten stated it had 5,739 base stations live in total offering mobile service to its users and expanding the reach of its radio network.

In Opensignal’s analytics we see the extent of this deployment. Across Japan’s cities we see the proportion of measurements taken when connected to Rakuten’s radio network expanding to more cities. In five cities, over half of measurements are on-net, and in a further nine cities over one quarter of measurements are on-net. But we also see differences based on how Rakuten has deployed its new network in each city.

In some cities, we see a much greater uplift in the on-net mobile experience than in others. For example, in Tokyo the on-net average Download Speed Experience of 36.6 Mbps is over twice as fast as the experience of Rakuten users when roaming of 18.1 Mbps. There is a similarly tremendous increase in a number of other cities, notably in Kawaguchi, Saitama, Funabashi, Kawasaki, Chiba, Kyoto, Yokohama and Hiroshima. However, in Nagoya and Osaka the difference between the on-net and roaming user experience is much narrower. These city variations likely reflect differences in either the amount of wireless spectrum Rakuten has deployed in each city, or in the quality of Rakuten’s backhaul network.

When we look at Upload Speed Experience by city, and compare roaming and on-net connectivity, we see an even more pronounced trend. In five cities — Tokyo, Kawaguchi, Funabashi, Kawasaki and Yokohama — the on-net Upload Speed Experience is, on average, more than three times faster than Rakuten users’ roaming experience. In ten of the fifteen cities we analyze here, Rakuten users’ on-net average Upload Speed Experience is faster than the average of the three established mobile operators (au, NTT DoCoMo and SoftBank).

Rakuten is clearly growing fast in both network reach and in user base. This means the ongoing flow of real-world analytics Opensignal can provide is invaluable to understand what is happening.

Rakuten is looking to use its Japanese network as a proof of concept for its different vendor approach and use of open network architectures and automation. The company aims to productize its solution as the Rakuten Communications Platform and offer it to other operators. As its Japanese business grows, we are seeing at scale the real experience this solution offers mobile users.