Methods and related devices for secondary node addition

Abstract

A mobile communication device and a method performed by a mobile communication device are provided. The method includes receiving, from a device, a Radio Resource Control (RRC) connection reconfiguration message when a Signaling Radio Bearer 3 (SRB3) connection with a secondary node has not been established, the RRC connection reconfiguration message including Secondary Cell Group (SCG) information; and initiating establishing the SRB3 connection with the secondary node according to the RRC connection reconfiguration message.

What is claimed is: 
     
         1 . A mobile communication device comprising:
 a receiver configured to receive a Radio Resource Control (RRC) connection reconfiguration message from a device when a Signaling Radio Bearer 3 (SRB3) connection with a secondary node has not been established, wherein the RRC connection reconfiguration message comprises Secondary Cell Group (SCG) information;   at least one processor coupled to the receiver; and   at least one memory coupled to the at least one processor, wherein the at least one memory stores one or more computer-executable instructions that, when executed by the at least one processor, cause the at least one processor to initiate establishing the SRB3 connection with the secondary node according to the RRC connection reconfiguration message.   
     
     
         2 . The mobile communication device according to  claim 1 , wherein the SCG information comprises an SRB3 configuration and a Service Data Adaptation Protocol (SDAP) configuration. 
     
     
         3 . The mobile communication device according to  claim 1 , wherein, when executed by the at least one processor, the one or more computer-executable instructions further cause the at least one processor to:
 initiate a secondary node addition procedure by transmitting a blind addition request to the device; and   receive a blind addition response from the device.   
     
     
         4 . The mobile communication device according to  claim 3 , wherein the blind addition response indicates at least one of:
 a maximum number of at least one cell identity (ID) in a cell selection result;   a maximum number of at least one zone ID in the cell selection result; and   a maximum number of at least one area ID in the cell selection result.   
     
     
         5 . A method performed by a mobile communication device, the method comprising:
 receiving, from a device, a Radio Resource Control (RRC) connection reconfiguration message when a Signaling Radio Bearer 3 (SRB3) connection with a secondary node has not been established, the RRC connection reconfiguration message comprising Secondary Cell Group (SCG) information; and   initiating establishing the SRB3 connection with the secondary node according to the RRC connection reconfiguration message.   
     
     
         6 . The method according to  claim 5 , wherein the SCG information comprises an SRB3 configuration and a Service Data Adaptation Protocol (SDAP) configuration. 
     
     
         7 . The method according to  claim 6 , wherein the SCG information further comprises at least one of a Packet Data Convergence Protocol (PDCP) configuration, a Radio Link Control (RLC) configuration, and a Medium Access Control (MAC) configuration. 
     
     
         8 . The method according to  claim 6 , further comprising:
 initiating a secondary node addition procedure by transmitting a blind addition request to the device in one of an RRC connection request message and an RRC connection resume request message; and   receiving a blind addition response from the device in one of an RRC connection setup message and an RRC connection resume message.   
     
     
         9 . The method according to  claim 8 , further comprising:
 transmitting a cell selection result to the device in one of an RRC connection setup complete message and an RRC connection resume complete message after transmitting the blind addition request.   
     
     
         10 . The method according to  claim 9 , wherein the cell selection result comprises one or more of at least one cell identity (ID), at least one zone ID and at least one area ID. 
     
     
         11 . The method according to  claim 10 , wherein the blind addition response indicates at least one of:
 a maximum number of the at least one cell ID in the cell selection result;   a maximum number of the at least one zone ID in the cell selection result; and   a maximum number of the at least one area ID in the cell selection result.