Handover method with link failure recovery, wireless device and base station for implementing such method

A user equipment (UE) for communication with a network having a plurality of base stations servicing respective cells, the UE comprising:

• a detector for detecting radio link failure between the UE and a source base station;
• a selector for selecting a cell for further communication with the network upon detection of the radio link failure;
• a request generator for generating a reestablishment request message to request a reestablishment of a radio link after the detection of the radio link failure,
• a transmitter adapted for transmitting the reestablishment request message to one of the base stations servicing the selected cell,
• wherein the reestablishment request message includes an identifier of the UE and a message authentication code for integrity (MAC-I) depending on a secret key available to the UE and the source base station and on an identity of the selected cell, and
• wherein the MAC-I is to be used for verifying the UE at the selected cell.

A base station for servicing at least one cell in a wireless communications system for communication with wireless devices, the base station comprising:

• a network interface adapted for receiving a first message from a source base station of the wireless communications system, the first message including an identifier of a wireless device having a radio link with the source base station and information for obtaining a first message authentication code for integrity (MAC-I) for said wireless device, wherein the first MAC-I depends on a secret key available to the wireless device and the source base station and on an identity of a target cell serviced by said base station;
• a wireless interface adapted for receiving a reestablishment request message from a wireless device when a radio link failure has occurred, the reestablishment request message including an identifier of said wireless device and a second MAC-I for said wireless device, wherein the second MAC-I depends on the secret key available to the wireless device and the source base station and on an identity of a selected cell selected by the wireless device;
• and
• a handover controller for transferring the communication link to said target cell if the wireless device identifier and the second MAC-I included in the reestablishment request message match the wireless device identifier and the first MAC-I obtained from said first message,
• wherein the reestablishment request message is received in order to permit a reestablishment of the radio link between the wireless device and the source base station.

A method for communicating with a network having a plurality of base stations servicing respective cells, the method being performed at a user equipment (UE), the method comprising:

• detecting radio link failure between the UE and a source base station;
• selecting a cell for further communication with the network after detection of the radio link failure;
• generating a reestablishment request message to request a reestablishment of a radio link after detection of the radio link failure;
• and
• transmitting the reestablishment request message to one of the base stations servicing the selected cell,
• wherein the reestablishment request message includes an identifier of the UE and a message authentication code for integrity (MAC-I) depending on a secret key available to the UE and the source base station and on an identity of the selected cell, and
• wherein the MAC-I is to be used for verifying the UE at the selected cell.