Method and apparatus for releasing connection with local gw when ue moves out of the residential/enterprise network coverage

Abstract

In some examples, a user equipment (UE) obtains a connectivity in a first cell, the connectivity comprising a first type of connection that provides access to services in a local data network. The UE camps on a second cell, determines if the connectivity is not supported in the second cell based on broadcast information from the second cell, the broadcast information comprising information of the second cell, and in response to determining that the connectivity is not supported in the second cell, disconnect the connectivity, wherein the disconnecting comprises sending a Non Access Stratum (NAS) message via the second cell.

1 . A method for use in a user equipment (UE) in idle mode and having at least one PDN connection comprising local internet protocol access (LIPA) connectivity or selected internet protocol traffic offload (SIPTO) connectivity at a first cell having a first cell characteristic, the method comprising;
 receiving an Access Stratum (AS) notification that the UE has moved into a second cell having a second cell characteristic; and   in response to the AS notification, sending a Non Access Stratum (NAS) message based on the second cell characteristic being different from a first cell characteristic.   
     
     
         2 . The method of  claim 1 , wherein each of the first and second cell characteristics comprises a closed subscriber group (CSG) ID, a cell id, or a Radio Access Technology (RAT) type. 
     
     
         3 . The method of  claim 2 , further comprising determining, by the UE, whether LIPA continuity is provided in the second cell based on:
 the CSG ID of the first cell being different from the CSG ID of the second cell,   the second cell being a non-CSG cell or not having a CSG ID, or   the UE moving to a different CSG cell with the same CSG ID of the first cell.   
     
     
         4 . The method of  claim 1 , wherein the UE comprises a Non-Access Stratum (NAS) layer, an Access Stratum (AS) layer, and an application layer. 
     
     
         5 . The method of  claim 1 , wherein sending the NAS message comprises:
 sending a TRACKING AREA UPDATE REQUEST message if the UE has at least one LIPA PDN connection and the AS notification indicates (1) that the second cell is a CSG cell having a CSG identity that is different from a CSG identity of the first cell, or (2) that the second cell is not a CSG cell.   
     
     
         6 . The method of  claim 1 , wherein sending the NAS message comprises:
 sending a PDN DISCONNECT REQ UEST message if the UE has at least two PDN connections and at least one PDN connection that is not a LIPA PDN connection and the AS notification indicates (1) that the second cell is a CSG cell having a CSG identity that is different from the CSG identity of the first cell, or (2) that the second cell is not a CSG cell.   
     
     
         7 . The method of  claim 1 , wherein sending the NAS messages comprises:
 sending a DETACH RESPONSE message in response to a DETACH REQUEST message if the U E has only LIPA PDN connections and the AS notification indicates (1) that the second cell is a CSG cell having a CSG identity that is different from the CSG identity of the first cell, or (2) that the second cell is not a CSG cell.   
     
     
         8 . The method of  claim 1 , wherein sending the NAS message comprises:
 sending a Tracking Area Update Request message or a PDN DISCONNECT REQUEST message if the UE is communicating with an Evolved Packet System (EPS) system and the first cell characteristic does not match the second cell characteristic.   
     
     
         9 . The method of  claim 1 , wherein sending the NAS message comprises:
 sending a Routing Area Update Request message or PDP Context Disconnect Request message if the UE is communicating with General Packet Radio Service (GPRS) system and the first cell characteristic does not match the second cell characteristic.   
     
     
         10 . The method of  claim 1 , further comprising starting a timer when the UE enters NAS idle mode having at least one active LIPA PDN connection, wherein the UE sends the NAS message after the timer expires only if the first cell characteristic and the second cell characteristic are different. 
     
     
         11 . The method of  claim 1 , further comprising starting a timer when the UE receives an Access Stratum (AS) notification that the UE has moved into the second cell that is (1) a CSG cell having a CSG identity that is different from a CSG identity of the first cell, or (2) not a CSG cell. 
     
     
         12 . The method of  claim 11 , wherein the UE sends the NAS message after the timer expires only if the first cell characteristic and the second cell characteristic are different. 
     
     
         13 . A user equipment (UE) comprising:
 at least one processor, wherein, while the UE is in an idle mode and has at least one PDN connection comprising local internet protocol access (LIPA) connectivity or selected internet protocol traffic offload (SIPTO) connectivity at a first cell having a first cell characteristic, the at least one processor is configured to:
 receive an Access Stratum (AS) notification that the UE has moved into a second cell having a second cell characteristic; and 
 in response to the AS notification, send a Non Access Stratum (NAS) message based on the second cell characteristic being different from a first cell characteristic. 
   
     
     
         14 . The UE of  claim 13 , wherein each of the first and second cell characteristics comprises a closed subscriber group (CSG) ID, a cell id, or a Radio Access Technology (RAT) type. 
     
     
         15 . The UE of  claim 14 , the at least one processor is configured to determine whether LIPA continuity is provided in the second cell based on:
 the CSG ID of the first cell being different from the CSG ID of the second cell,   the second cell being a non-CSG cell or not having a CSG ID, or   the UE moving to a different CSG cell with the same CSG ID of the first cell.   
     
     
         16 . The UE of  claim 13 , wherein the UE comprises a Non-Access Stratum (NAS) layer, an Access Stratum (AS) layer, and an application layer. 
     
     
         17 . The UE of  claim 13 , wherein sending the NAS message comprises:
 sending a TRACKING AREA UPDATE REQUEST message if the UE has at least one LIPA PDN connection and the AS notification indicates (1) that the second cell is a CSG cell having a CSG identity that is different from a CSG identity of the first cell, or (2) that the second cell is not a CSG cell.   
     
     
         18 . The UE of  claim 13 , wherein sending the NAS message comprises:
 sending a PDN DISCONNECT REQ UEST message if the UE has at least two PDN connections and at least one PDN connection that is not a LIPA PDN connection and the AS notification indicates (1) that the second cell is a CSG cell having a CSG identity that is different from the CSG identity of the first cell, or (2) that the second cell is not a CSG cell.   
     
     
         19 . The UE of  claim 13 , wherein sending the NAS messages comprises:
 sending a DETACH RESPONSE message in response to a DETACH REQUEST message if the U E has only LIPA PDN connections and the AS notification indicates (1) that the second cell is a CSG cell having a CSG identity that is different from the CSG identity of the first cell, or (2) that the second cell is not a CSG cell.   
     
     
         20 . The UE of  claim 13 , wherein sending the NAS message comprises:
 sending a Tracking Area Update Request message or a PDN DISCONNECT REQUEST message if the UE is communicating with an Evolved Packet System (EPS) system and the first cell characteristic does not match the second cell characteristic.   
     
     
         21 . The UE of  claim 13 , wherein sending the NAS message comprises:
 sending a Routing Area Update Request message or PDP Context Disconnect Request message if the UE is communicating with General Packet Radio Service (GPRS) system and the first cell characteristic does not match the second cell characteristic.   
     
     
         22 . The UE of  claim 13 , wherein the at least one processor is configured to start a timer when the UE enters NAS idle mode having at least one active LIPA PDN connection, wherein the UE sends the NAS message after the timer expires only if the first cell characteristic and the second cell characteristic are different. 
     
     
         23 . The UE of  claim 13 , wherein the at least one processor is configured to start a timer when the UE receives an Access Stratum (AS) notification that the UE has moved into the second cell that is (1) a CSG cell having a CSG identity that is different from a CSG identity of the first cell, or (2) not a CSG cell. 
     
     
         24 . The UE of  claim 23 , wherein the at least one processor sends the NAS message after the timer expires only if the first cell characteristic and the second cell characteristic are different. 
     
     
         25 . A non-transitory storage medium storing instructions that upon execution cause a user equipment (UE), while the UE is in an idle mode and has at least one PDN connection comprising local internet protocol access (LIPA) connectivity or selected internet protocol traffic offload (SIPTO) connectivity at a first cell having a first cell characteristic, to:
 receive an Access Stratum (AS) notification that the UE has moved into a second cell having a second cell characteristic; and   in response to the AS notification, send a Non Access Stratum (NAS) message based on the second cell characteristic being different from a first cell characteristic.