US Patent No. 10,798,768

RADIO TERMINAL AND BASE STATION


Patent No. 10,798,768
Issue Date October 06, 2020
Title Radio Terminal And Base Station
Inventorship Masato Fujishiro, Yokohama (JP)
Yushi Nagasaka, Ritto (JP)
Henry Chang, San Diego, CA (US)
Assignee KYOCERA Corporation, Kyoto (JP)

Claim of US Patent No. 10,798,768

2. A method performed at a radio terminal that performs traffic steering for transferring traffic between the radio terminal and a core network from a Wireless Wide Area Network (WWAN) to a Wireless Local Area Network (WLAN), comprising:in an Access Stratum (AS) entity that performs communication with a base station of the WWAN,
receiving, from the base station, configuration information including a steering command instructing the traffic steering;
providing, to a Non-Access Stratum (NAS) entity positioned at a higher layer than the AS entity, a first notification indicating that traffic has to be transferred to the WLAN, in response to reception of the steering command;
transmitting, to the base station, a report indicating that connection to the WLAN has failed, in response to a failure in the connection to the WLAN after receiving the steering command; and
in response to the failure in the connection to the WLAN, releasing the configuration information while providing, to the NAS entity, a second notification indicating that traffic has to be returned from the WLAN, wherein
the radio terminal is in a radio resource control (RRC) connected state and is configured with a WWAN-WLAN aggregation from the base station of the WWAN,
the radio terminal is configured to be able to use a resume procedure, and
the method further comprises:
when a WLAN communication is resumed from a state where the WLAN communication is unavailable to a state where the WLAN communication is available, transmitting WLAN connection status report including resumption of WLAN communication as information element, to the base station of the WWAN.