'JAPAN Roaming' begins today to let carriers share networks during disasters

JAPAN Roaming started on April 1 to allow Japanese mobile carriers to share networks during large disasters or outages.

NTT Docomo, SoftBank, KDDI (Okinawa Cellular) and Rakuten Mobile are participating in the program.

Carriers will provide 4G LTE to affected carriers' users at the municipality level using two modes: emergency-calls-only or full roaming.

Full roaming includes voice calls, SMS and up to 300 kbps uplink/downlink data, and mode selection is decided by carrier consultation.