Offline device paging

Abstract

The network resources allocated to Machine Type Communication (MTD) devices (also referred to as Machine-to-Machine (M2M) Devices) can be reduced through the introduction of a new device state in a network. The network device state, referred to as a sleep state, allows the network to offload context information about the device to another network element so that the resources allocated to the sleeping device can be released. When the device needs to be contacted by a network element, the stored context information can be retrieved to facilitate paging the otherwise offline device.

What is claimed is: 
     
         1 . A method of managing resources allocated to user equipment in a network, the method comprising:
 receiving, from a user equipment over a radio access network, an indication that the user equipment is entering a low traffic state;   transferring context information associated with the user equipment to a secondary storage; and   de-allocating network resources associated with the user equipment in response to the receipt of the indication.   
     
     
         2 . The method of  claim 1  wherein the step of receiving includes receiving a SLEEP request message. 
     
     
         3 . The method of  claim 1  wherein the step of receiving further includes receiving an indication that the user equipment is unlikely to change network cells. 
     
     
         4 . The method of  claim 1  wherein the step of transferring includes transferring the context information to an external secondary storage. 
     
     
         5 . The method of  claim 4  wherein the step of transferring includes transmitting context information stored in a local primary storage to the secondary storage residing in a Machine Type Communication Tracking Server. 
     
     
         6 . The method of  claim 1  wherein the step of de-allocating network resources includes discarding a portion of the context information transferred to the secondary storage. 
     
     
         7 . The method of  claim 1  wherein the step of de-allocating network resources includes keeping a first part of the context information transferred to secondary storage, and discarding a second part of the context information transferred to secondary storage. 
     
     
         8 . The method of  claim 7  wherein the step of de-allocating network resources includes transmitting a message to an external node instructing the external node to release resources allocated to the user equipment. 
     
     
         9 . A node for storing context information about user equipment connected to a radio access network, the node comprising:
 a primary storage for storing context information associated with user equipment;   a radio interface for receiving requests transmitted over a radio access network from user equipment;   a network interface for communicating with external nodes; and   a processor for receiving, from a user equipment over the radio interface, an indication that the user equipment is entering a low traffic state, for transmitting to a secondary storage context information associated with the user equipment stored in the primary storage, for deleting at least part of the context information transmitted to the secondary storage from the primary storage, and for transmitting a request to at least one external node over the network interface to release resources allocated to the user equipment in response to the receipt of the indication.   
     
     
         10 . The node of  claim 10  wherein the radio interface is a network interface connecting the node to a radio access network basestation.