Security mode configuration procedures in wireless devices

A wireless communications device arranged to detect an error in a security mode configuration procedure conducted at a radio access network in wireless communication with the wireless communication device, the wireless communication device comprising:

• a transceiver arranged to transmit from the wireless communication device a cell update message to the radio access network, the cell update message transmitted to cause the radio access network to abort a security mode configuration procedure which is to replace an original security mode configuration with a new security mode configuration;
• a central processing unit;
• and
• a memory coupled to the central processing unit, the memory containing program code executable by the central processing unit causing the central processing unit to perform the following steps:
• receive, after the transmission of said update message, the new security mode configuration and completing a security mode configuration procedure at the wireless communication device to replace the original security mode configuration with the new security mode configuration;
• and thereafter
• receive a downlink message from the radio access network;
• perform a security mode configuration check on the received downlink message using said new security mode configuration;
• in the event that the security mode configuration check fails, perform a further security mode configuration check on the downlink message to detect an error in the security mode configuration procedure, wherein the step of performing a further security mode configuration check comprises the wireless communication device using said original security mode configuration or checking that the received downlink message is a first downlink message checked using said new security mode configuration;
• and
• when the further security mode configuration check detects an error in the security mode configuration procedure, perform security mode configuration checks on further downlink messages from the network using the original security mode configuration thereby resolving any security code mismatch between the wireless communication device and the radio access network and preventing any loss of the wireless communication.

A method of performing, at a wireless communication device, an error recovery in the event of detecting an error in a security mode configuration procedure conducted at a radio access network in wireless communication with the wireless communication device in accordance with a multi-layered communication protocol, the method comprising:

• receiving, at the wireless communication device, a downlink message from the wireless communication network effected by a signaling connection at a Radio Resource Control (RRC) layer of the multi-layered communication protocol between the wireless communication device and the wireless communication network;
• performing a security mode configuration check on the received downlink message;
• in the event that the security mode configuration check fails, determining that there has been an error in a security mode configuration procedure for replacing an original security mode configuration with a new security mode configuration, wherein the step of determining whether there has been an error in a security mode configuration procedure comprises the wireless communication device using said original security mode configuration or checking that the received downlink message is a first downlink message checked using said new security mode configuration;
• in response to that determination, releasing at the wireless communication device the signaling connection at the RRC layer to the wireless communication network without initiating a Radio Link Control (RLC) reset procedure;
• and
• beginning establishment of a new signaling connection at the RRC layer to the wireless communication network thereby resolving any security code mismatch between the wireless communication device and the radio access network and preventing any loss of the RRC connection.