Rakuten Mobile Completes Connection of MMEs with KDDI Roaming Areas Through S10 Interface

Tokyo, April 14, 2020 - Rakuten Mobile, Inc. today announced that it has completed the connection of mobility management entities (MMEs) with KDDI Corporation for its 4th generation mobile communications (LTE communications) roaming services, through the S10 interface*1.

Rakuten Mobile offers its carrier service through its own network area, alongside roaming services provided by KDDI Corporation in other areas. By connecting both companies’ MMEs through the S10 interface, in addition to the existing S8 interface*2 connection, the time taken to switch networks is reduced, and voice calls will no longer drop out during the network switchover as customers move between the network and roaming areas. This eliminates the need for customers to redial for voice calls after crossing borders between network and roaming areas, allowing Rakuten Mobile to provide an enhanced mobile experience to its customers.

Through collaboration between Rakuten Mobile and Cisco Systems G.K. on development, supported by the cooperation of KDDI Corporation, the companies have successfully connected the MMEs of different mobile network operators to realize a greater level of convenience for customers.

Diagram of the Rakuten Mobile roaming configuration

Rakuten Mobile will continue to work to create safe, secure and easy-to-use mobile services that offer a greater level of convenience to the lives of its customers.

*1 The S10 interface is a device interface standard established by 3GPP (3rd Generation Partnership Project). The interface is used to connect MMEs (mobility management entities), the control equipment in the network core.
*2 The S8 interface is a device interface standard established by 3GPP. The interface is the system used in connecting SAEGW (System Architecture Evolution Gateway).
*3 The System Architecture Evolution Gateway (SAEGW) is equipment located in the core network for transferring user data.