Method and arrangement for managing security reconfiguration in a cellular communication system

Abstract

Methods are discussed of managing security reconfiguration and cell update procedures in a user equipment and in a node in a cellular communication system and a user equipment and a node in the cellular communication system. Methods in the user equipment may include detecting a cell update trigger event, and aborting any ongoing security reconfiguration procedure in the user equipment in response to the detected cell update trigger event. Subsequently, a security status indication in response to the aborted security reconfiguration may be provided, and a cell update message and the provided security status indication may be jointly transmitted to a node.

1 . A method of managing security reconfiguration and cell update procedures in a user equipment in a cellular communication system, the method comprising:
 detecting a cell update trigger event;   aborting an ongoing security reconfiguration procedure in the user equipment in response to detecting the cell update trigger event;   setting a security status indication to a predetermined value in response to aborting the security reconfiguration; and   jointly transmitting a cell update message and the security status indication to a node.   
     
     
         2 . The method according to  claim 1 , further comprising:
 prior to detecting the cell update trigger event, receiving a security reconfiguration request from a node; and   initiating and confirming the requested security reconfiguration, wherein the security status indication informs about the confirmed security reconfiguration being aborted.   
     
     
         3 . The method according to  claim 2 , wherein jointly transmitting the cell update message and the provided security status indication comprises transmitting the cell update message and the provided security status indication in a same cell update message. 
     
     
         4 . The method according to  claim 3 , wherein the security status indication is provided as a Boolean information element in the cell update message. 
     
     
         5 . A user equipment in a cellular communication system comprising:
 a processor; and   a memory device coupled to the processor having instructions stored therein that are executable by the processor for causing the user equipment to:
 detect a cell update trigger event; 
 abort an ongoing security reconfiguration procedure in the user equipment in response to detecting the cell update trigger event; 
 set a security status indication to a predetermined value in response to aborting the security reconfiguration; and 
 jointly transmit a cell update message and the security status indication to a node. 
   
     
     
         6 . The user equipment according to  claim 5 , wherein the instructions are further executable by the processor for causing the user equipment to:
 receive a security reconfiguration request from a node; and   initiate and confirm the requested security reconfiguration.   
     
     
         7 . A cellular communication system operable to manage security reconfiguration and cell update procedures in a user equipment (“UE”), the cellular communication system comprising:
 the UE configured to:
 detect a cell update trigger event; 
 abort an ongoing security reconfiguration procedure in the user equipment in response to detecting the cell update trigger event; 
 set a security status indication to a predetermined value in response to aborting the security reconfiguration; and 
 jointly transmit a cell update message and the security status indication to a node; and 
 
 the network node communicatively coupled to the user equipment and configured to:
 receive the cell update message and security status indication from the UE; and 
 manage security reconfiguration based on the received security status indication. 
 
 
     
     
         8 . The cellular communication system of  claim 7 , wherein the UE is further configured to:
 receive a security reconfiguration request from the network node; and   initiate and confirm the requested security reconfiguration.   
     
     
         9 . The cellular communication system of  claim 8 , wherein the network node is further configured to:
 transmit a security reconfiguration request;   receive a security reconfiguration confirmation; and   perform security reconfiguration.