# US 11,310,704 B2 · Secondary communication node change > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,704 B2 - Document ID: US11310704B2 - Status: Granted - Kind: B2 - Application number: 17/037,281 - Filed: 2020-09-29 - Published: 2021-01-14 - Granted: 2022-04-19 - Earliest claimed: 2018-03-30 - Assignees: Zte Corporation - Applicants: ZTE Corporation - Inventors: Jianmin Fang; He Huang - Web page: https://patentgrep.com/patent/US11310704B2 ## CPC - H04W 76/25: Maintenance of established connections - H04W 36/00695: {using split of the control plane or user plane} - H04W 36/0079: {in case of hand-off failure or rejection} - H04W 36/08: Reselecting an access point - H04W 76/15: Setup of multiple wireless link connections - H04W 76/18: Management of setup rejection or failure - H04W 76/19: Connection re-establishment - Y02D 30/70: in wireless communication networks - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract Methods, systems, and devices related to mobility robustness in dual connectivity mode are described. In one representative aspect, a method for wireless communication includes receiving, at a master communication node, a first message from a first secondary communication node requesting a change from a first connection to a second connection. The method includes transmitting a second message to the second secondary communication node to request establishing the second connection. The method includes receiving a third message from the mobile device confirming a configuration of the second connection. The method includes receiving a fourth message from the mobile device indicating a failure of the second connection. The method further includes transmitting a fifth message to the first secondary communication node to report that the change from the first connection to the second connection is an improper change. ## Claims ### Claim 1 A method of wireless communication, receiving, at a master communication node, a first message from a first secondary communication node requesting a change from a first connection between a mobile device and the first secondary communication node to a second connection between the mobile device and a second secondary communication node, wherein the first message includes information identifying the second secondary communication node; transmitting, from the master communication node, a second message to the second secondary communication node to request establishing the second connection between the mobile device and the second secondary communication node; receiving, at the master communication node, a third message from the mobile device confirming a configuration of the second connection between the mobile device and the second secondary communication node; receiving at the master communication node, a fourth message from the mobile device indicating a failure of the second connection between the mobile device and the second secondary communication node; and transmitting, from the master communication node, a fifth message to the first secondary communication node reporting that the change from the first connection to the second connection is an improper change. ### Claim 2 (depends on 1) The method of claim 1, comprising: determining, by the master communication node, to change from the second connection between the mobile device and the second secondary communication node to a third connection between the mobile device and a third secondary communication node. ### Claim 3 (depends on 2) The method of claim 2, wherein the determining to change from the second connection to the third connection comprises: receiving, at the master communication node, a sixth message from the second secondary communication node, the sixth message requesting to change the second connection to the third connection, wherein the sixth message includes information identifying the third secondary communication node. ### Claim 4 (depends on 2) The method of claim 2, wherein the determining to change from the second connection to the third connection comprises: identifying, by the master communication node, based on measurement results included in the fourth message, the third secondary communication node to be used for establishing the third connection. ### Claim 5 (depends on 1) The method of claim 1, wherein the master communication node indicates the improper change from the first connection to the second connection using one of the following types of reason codes: Wrong Secondary Node Change, Too Early Secondary Node Change, Too Late Secondary Node Change, or Ping-Pong Secondary Node Change. ### Claim 6 A method for wireless communication, comprising: transmitting, from a first secondary communication node, a first message to a master communication node to request a change from a first connection between a mobile device and the first secondary communication node to a second connection between the mobile device and a second secondary communication node; receiving, at the first secondary communication node, a second message from the master communication node confirming the change from the first connection to the second connection; receiving, at the first secondary communication node, a third message indicating a failure of the second connection between the mobile device and the second secondary communication node; and determining, by the first secondary communication node based on the third message that the change from the first connection to the second connection is an improper change. ### Claim 7 (depends on 6) The method of claim 6, wherein the third message is received from the second secondary communication node, the third message including information for reporting that the change from the first connection to the second connection is an improper change. ### Claim 8 (depends on 6) The method of claim 6, wherein the third message is received from the master communication node, and wherein the method further comprises: transmitting, from the first secondary communication node prior to determining the improper change, a fourth message to the second secondary communication node indicating the failure of the second connection between the mobile device and the secondary communication node; and receiving, at the first secondary communication node, a fifth message from the second secondary communication node reporting that the change from the first connection to the second connection is an improper change. ### Claim 9 (depends on 6) The method of claim 6, wherein the improper change from the first connection to the second connection is indicated using one of the following types of reason codes: Wrong Secondary Node Change, Too Early Secondary Node Change, Too Late Secondary Node Change, or Ping-Pong Secondary Node Change. ### Claim 10 (depends on 6) The method of claim 6, wherein the improper change from the first connection to the second connection is indicated using a Too Early Secondary Node Change reason code or a Wrong Secondary Node Change reason code. ### Claim 11 An apparatus for wireless communication, comprising: a processor; and a memory including processor executable code, wherein the processor executable code upon execution by the processor configures the processor to: receive a first message from a first secondary communication node requesting a change from a first connection between a mobile device and the first secondary communication node to a second connection between the mobile device and a second secondary communication node, wherein the first message includes information identifying the second secondary communication node; transmit a second message to the second secondary communication node to request establishing the second connection between the mobile device and the second secondary communication node; receive a third message from the mobile device confirming a configuration of the second connection between the mobile device and the second secondary communication node; receive a fourth message from the mobile device indicating a failure of the second connection between the mobile device and the second secondary communication node; and transmit a fifth message to the first secondary communication node reporting that the change from the first connection to the second connection is an improper change. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the processor is configured to: determine to change from the second connection between the mobile device and the second secondary communication node to a third connection between the mobile device and a third secondary communication node. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the processor is configured to: receive a sixth message from the second secondary communication node, the sixth message requesting to change the second connection to the third connection, wherein the sixth message includes information identifying the third secondary communication node. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the processor is configured to: identify, based on measurement results included in the fourth message, the third secondary communication node to be used for establishing the third connection. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the processor is configured to indicate the improper change from the first connection to the second connection using one of the following types of reason codes: Wrong Secondary Node Change, Too Early Secondary Node Change, Too Late Secondary Node Change, or Ping-Pong Secondary Node Change. ### Claim 16 An apparatus for wireless communication, comprising: a processor; and a memory including processor executable code, wherein the processor executable code upon execution by the processor configures the processor to: transmit a first message to a master communication node to request a change from a first connection between a mobile device and the first secondary communication node to a second connection between the mobile device and a second secondary communication node; receive a second message from the master communication node confirming the change from the first connection to the second connection; receive a third message indicating a failure of the second connection between the mobile device and the second secondary communication node; and determine, based on the third message that the change from the first connection to the second connection is an improper change. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the processor is configured to receive the third message from the second secondary communication node, the third message including information for reporting that the change from the first connection to the second connection is an improper change. ### Claim 18 (depends on 16) The apparatus of claim 16, wherein the processor is configured to receive the third message from the master communication node, the method further configured to: transmit, prior to determining the improper change, a fourth message to the second secondary communication node indicating the failure of the second connection between the mobile device and the secondary communication node; and receive a fifth message from the second secondary communication node reporting that the change from the first connection to the second connection is an improper change. ### Claim 19 (depends on 16) The apparatus of claim 16, wherein the improper change from the first connection to the second connection is indicated using one of the following types of reason codes: Wrong Secondary Node Change, Too Early Secondary Node Change, Too Late Secondary Node Change, or Ping-Pong Secondary Node Change. ### Claim 20 (depends on 16) The apparatus of claim 16, wherein the improper change from the first connection to the second connection is indicated using a Too Early Secondary Node Change reason code or a Wrong Secondary Node Change reason code.