Network node, a wireless device and methods therein for handling radio access network (RAN) context information in a wireless communications network

A base station configured to communicate with a user equipment served by the base station in a wireless communications network, wherein

• the base station is configured to determine that the user equipment is no longer in a connected state in a cell when the base station:
• releases the user equipment from the connected state to an idle state in the cell, or
• performs a handover of the user equipment device to another cell in the wireless communications network, or
• releases the user equipment to be served in another cell in the wireless communications network, or
• detects a radio link failure associated with the user equipment;
• the base station is configured to store a Radio Access Network (RAN) context information of the user equipment when the user equipment is no longer in the connected state in the cell, the base station comprising:
• a receiver configured to receive information indicating the RAN context information from the user equipment when the user equipment has returned to the connected state in the cell, and
• a transmitter configured to transmit, to the user equipment, information indicating that the user equipment is to use the indicated RAN context information in the cell when the indicated RAN context information is such that it can be reused with the RAN context information of the user equipment previously stored by the base station.

A method performed by a user equipment configured to communicate with a base station in a wireless communications network, the method comprising

• determining that the user equipment is no longer in a connected state in a cell when the base station:
• releases the user equipment from the connected state to an idle state in the cell, or
• performs a handover of the user equipment to another cell in the wireless communications network, or
• releases the user equipment to be served in another cell in the wireless communications network, or
• detects a radio link failure associated with the user equipment;
• storing a Radio Access Network (RAN) context information of the user equipment when the user equipment is no longer in the connected state in the cell;
• transmitting, to the base station, information indicating the stored RAN context information when the user equipment returns to a connected state in the cell;
• and
• receiving, from the base station, information indicating that the user equipment is to use the stored RAN context information.

A user equipment configured to communicate with a base station in a wireless communications network, wherein

• the user equipment is configured to store a Radio Access Network (RAN) context information of the user equipment when no longer in a connected state in a cell, wherein the user equipment is no longer in the connected state in the cell when the base station:
• releases the user equipment from the connected state to an idle state in the cell, or
• performs a handover of the user equipment to another cell in the wireless communications network, or
• releases the user equipment to be served in another cell in the wireless communications network, or
• detects a radio link failure associated with the user equipment,
• the user equipment comprising:
• a transmitter configured to transmit, to the base station, information indicating the stored RAN context information when the user equipment returns to the connected state in the cell;
• and
• a receiver configured to receive, from the base station, information indicating that the user equipment is to use the stored RAN context information.