# US 2019/0380108 A1 · Master base station, secondary base station, and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0380108 A1 - Document ID: US20190380108A1 - Status: Published application - Kind: A1 - Application number: 16/426,145 - Filed: 2019-05-30 - Published: 2019-12-12 - Earliest claimed: 2018-06-07 - Assignees: NEC Corporation - Applicants: NEC Corporation - Inventors: Masahiro KOMATSU - Web page: https://patentgrep.com/patent/US20190380108A1 ## CPC - H04W 68/005: {Transmission of information for alerting of incoming communication} - H04L 1/1642: {Formats specially adapted for sequence numbers} - H04L 1/1678: {where the control information is for timing, e.g. time stamps} - H04L 1/1685: {the supervisory signal being transmitted in response to a specific request, e.g. to a polling signal} - H04W 56/003: {Arrangements to increase tolerance to errors in transmission or reception timing} - H04W 56/005: {compensating for timing error by adjustment in the receiver} - H04W 80/02: Data link layer protocols - H04W 80/08: Upper layer protocols {(network arrangements or communication protocols for networked applications H04L67/00)} - H04W 84/20: Leader-follower arrangements - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract An example object of the present application is to enable a master base station to obtain, at an appropriate timing, a transmission status or a delivery status of data transmitted from a secondary base station to a terminal apparatus. There is provided a master base station 100 including: a controller configured to: obtain a message that requests a notification relating to a status of at least one of a data transmission status from a secondary base station 200 to a terminal apparatus 300 and a data delivery status from the secondary base station 200 to the terminal apparatus 300; and transmit the message to the secondary base station 200. The message includes timing indication information that indicates a timing of the notification to the secondary base station 200. ## Claims ### Claim 1 A master base station which performs wireless communication with a terminal apparatus, the master base station comprising: a controller configured to: obtain a message that requests a notification from a secondary base station which performs wireless communication with the terminal apparatus, the notification relating to a status of at least one of a data transmission status from the secondary base station to the terminal apparatus and a data delivery status from the secondary base station to the terminal apparatus; and transmit the message to the secondary base station, wherein the message includes timing indication information that indicates a timing of the notification to the secondary base station. ### Claim 2 (depends on 1) The master base station according to claim 1, wherein the timing indication information indicates that the timing of the notification is when the data transmission status is updated. ### Claim 3 (depends on 1) The master base station according to claim 1, wherein the timing indication information indicates that the timing of the notification is when the data delivery status is updated. ### Claim 4 (depends on 3) The master base station according to claim 3, wherein the data delivery status is updated in response to a status report being received by the secondary base station from the terminal apparatus. ### Claim 5 (depends on 1) The master base station according to claim 1, wherein: a sequence number allocated by the master base station is set for data to be transmitted from the secondary base station to the terminal apparatus; and the message includes sequence number indication information that indicates a sequence number that is a target of notification relating to a status of at least one of the data transmission status and the data delivery status. ### Claim 6 (depends on 1) The master base station according to claim 1, wherein the data transmission status is a data transmission status at a Radio Link Control (RLC) layer. ### Claim 7 (depends on 1) The master base station according to claim 1, wherein the data delivery status is a data delivery status at a Radio Link Control (RLC) layer. ### Claim 8 A secondary base station which performs wireless communication with a terminal apparatus, the secondary base station comprising: a controller configured to: receive a message from a master base station which performs wireless communication with the terminal apparatus, the message requesting a notification relating to a status of at least one of a data transmission status from the secondary base station to the terminal apparatus and a data delivery status from the secondary base station to the terminal apparatus; and transmit information to the master base station in accordance with the message, the information relating to a status of at least one of the data transmission status and the data delivery status, wherein the message includes timing indication information that indicates a timing of the notification to the secondary base station, and the controller is configured to transmit the information relating to a status of at least one of the data transmission status and the data delivery status to the master base station at the timing indicated by the timing indication information. ### Claim 9 A method performed by a master base station which performs wireless communication with a terminal apparatus, the method comprising: obtaining a message that requests a notification from a secondary base station which performs wireless communication with the terminal apparatus, the notification relating to a status of at least one of a data transmission status from the secondary base station to the terminal apparatus and a data delivery status from the secondary base station to the terminal apparatus; and transmitting the message to the secondary base station, wherein the message includes timing indication information that indicates a timing of the notification to the secondary base station.