Bearer management

Abstract

A method is provided of establishing a bearer in a packet switched mobile wireless network comprising a mobile device and a network node, and a corresponding network. Bearer information is sent indicating predetermined maximum number of bearers, remaining number of bearers, or that no more bearers can be established. If no more bearers can be established and a further bearer is required, a previously established bearer is released. If required, a bearer synchronization procedure is performed. A further bearer is then established or, if the mobile device determines that an emergency connection is required, a request is sent for a further bearer to the network node. If a current number of bearers established for the mobile device equals the maximum number of bearers, the network node releases a previously established bearer establish a bearer for an emergency connection.

What is claimed: 
     
         1 . A method of establishing a bearer in a packet switched mobile wireless communications network comprising a mobile device and a network node, wherein a predetermined maximum number of bearers can be established for the mobile device within the network, the method comprising:
 determining at the mobile device that an emergency PDN connection is required; and   sending a request for a further bearer from the mobile device to the network node;   wherein if a current number of bearers established for the mobile device is equal to the maximum number of bearers, the method further comprises:   releasing, at the network node, a bearer previously established for the mobile device within the network; and   establishing a bearer for an emergency PDN connection for the mobile device within the network.   
     
     
         2 . The method of  claim 1 , wherein releasing, at the network node, a bearer previously established for the mobile device within the network comprises selecting at the network node a bearer for release which is not for an emergency PDN connection. 
     
     
         3 . The method of  claim 1 , further comprising:
 performing a bearer synchronization procedure between the mobile device and the network node after the emergency PDN connection has ended.   
     
     
         4 . The method of  claim 3 , further comprising:
 sending from the network node to the mobile device an indication that a bearer synchronization procedure is required while establishing the bearer for the emergency PDN connection; and   initiating at the mobile device the bearer synchronization procedure after the emergency PDN connection has ended.   
     
     
         5 . The method of  claim 3 , further comprising:
 sending from the network node to the mobile device an indication that a bearer synchronization procedure is required in a separate session management message; and   initiating at the mobile device the bearer synchronization procedure after the emergency PDN connection has ended.   
     
     
         6 . The method of  claim 1 , further comprising:
 initiating at the network node an explicit bearer deactivation procedure between the network node and the mobile device after the bearer for the emergency PDN connection has been established.   
     
     
         7 . The method of  claim 1  further comprising:
 sending from the network node a session management status request containing the bearer identification of the bearer released by the network; and 
 receiving at the mobile device the session management status request and deactivating the bearer locally in the mobile device. 
 
     
     
         8 . A method of establishing a bearer within a network node in a packet switched mobile wireless communications network which further comprises a mobile device, wherein a predetermined maximum number of bearers can be established for the mobile device within the network, the method comprising:
 receiving a request for a further bearer from the mobile device;   wherein if a current number of bearers established for the mobile device is equal to the maximum number of bearers, the method further comprises:   releasing a bearer previously established for the mobile device within the network; and   establishing a bearer for an emergency PDN connection for the mobile device within the network.