Network apparatus and process to determine the connection context for connections used for (local) offloading

Abstract

A method, system and device are provided for managing LIPA and/or SIPTO connection releases by providing predetermined context information in either the context request message or response thereto exchanged between source and target Mobility Management Entity (MME) devices to allow the appropriate MME device to determine if LIPA service continuity is provided or not.

What is claimed is: 
     
       1. A first network element capable of offloading user plane traffic, the first network element comprising:
 a memory; and 
 at least one processor coupled to the memory and configured to:
 receive a first message comprising a first NAS request message that is received from a UE, the first message including one or more first indicators, the one or more first indicators comprising a first identifier of a third network element that is part of a local network; 
 send a context request message to a second network element, wherein the first network element is different from each of the second network element and the UE; 
 receive a response to the context request message, the response including information for one or more Packet Data Network (PDN) connections, the response including one or more second indicators associated with at least one of the one or more PDN connections, the one or more second indicators comprising a second identifier of the third network element that is part of a local network; 
 compare the one or more first indicators with the one or more second indicators, wherein the comparing comprises determining whether the first identifier matches the second identifier; 
 in response to determining that the first identifier does not match the second identifier, send a second message to the UE, wherein the second message is at least one of (a) a response to the first NAS request message or a second NAS request message or (b) a third message associated with performing a Detach Procedure initiated by the first network element; and 
 in response to determining that the first identifier matches the second identifier, determine that dedicated bearers or a secondary Packet Data Protocol (PDP) context for user plane traffic routed to a local gateway are not supported, 
 
 wherein the one or more PDN connections are activated subsequent to receiving a request from a fourth network element that is part of a local network, and wherein the request from the fourth network element comprises another NAS message from the UE and the one or more second indicators. 
 
     
     
       2. The first network element of  claim 1 , wherein the first NAS request message is one of a Tracking Area Update (TAU) request message or a Routing Area Update (RAU) request message. 
     
     
       3. The first network element of  claim 1 , wherein the response to the first NAS request message or the second NAS request message is one of:
 a response to a TAU request message; 
 a response to a RAU request message; or 
 a response to a request for the dedicated bearers or the secondary PDP context, the dedicated bearers or the secondary PDP context associated with the user plane traffic routed to the local gateway. 
 
     
     
       4. The first network element of  claim 2 , wherein the response to the first NAS request message is one of:
 a TAU message comprising a reject message with a cause code; or 
 a RAU message comprising a reject message with a cause code. 
 
     
     
       5. The first network element of  claim 1 , wherein the sending the third message associated with performing the Detach Procedure is based on said determining that the first identifier does not match the second identifier. 
     
     
       6. The first network element of  claim 1 , wherein the determining that the dedicated bearers or the secondary PDP context are not supported is based on subscription information received from a subscription database. 
     
     
       7. The first network element of  claim 1 , wherein the comparing of the one or more first indicators with the one or more second indicators comprises a determination that none of the one or more first indicators matches the one or more second indicators. 
     
     
       8. The first network element of  claim 1 , wherein the comparing of the one or more first indicators with the one or more second indicators comprises a determination that at least one of the one or more first indicators fails to match at least one of the one or more second indicators. 
     
     
       9. A method of offloading user plane traffic, comprising:
 receiving, by a first network element, a first message comprising a first NAS request message that is received from a UE, the first message including one or more first indicators, the one or more first indicators comprising a first identifier of a third network element that is part of a local network; 
 sending, by the first network element, a context request message to a second network element, wherein the first network element is different from each of the second network element and the UE; 
 receiving, by the first network element, a response to the context request message, the response including information for one or more Packet Data Network (PDN) connections, the response including one or more second indicators associated with at least one of the one or more PDN connections, the one or more second indicators comprising a second identifier of the third network element that is part of a local network; 
 comparing, by the first network element, the one or more first indicators with the one or more second indicators, wherein the comparing comprises determining whether the first identifier matches the second identifier; 
 in response to determining that the first identifier does not match the second identifier, sending, by the first network element, a second message to the UE, wherein the second message is at least one of (a) a response to the first NAS request message or a second NAS request message or (b) a third message associated with performing a Detach Procedure initiated by the first network element; and 
 in response to determining that the first identifier matches the second identifier, determining that dedicated bearers or a secondary Packet Data Protocol (PDP) context for user plane traffic routed to a local gateway are not supported, 
 wherein the one or more PDN connections are activated subsequent to receiving a request from a fourth network element that is part of a local network, and wherein the request from the fourth network element comprises another NAS message from the UE and the one or more second indicators. 
 
     
     
       10. The first network element of  claim 1 , wherein the first and second network elements are network elements of a core network. 
     
     
       11. The first network element of  claim 1 , wherein the first and second network elements are respectively first and second Mobility Management Entities (MMEs). 
     
     
       12. The first network element of  claim 1 , wherein the context request message is to obtain an evolved packet system (EPS) bearer context for the UE. 
     
     
       13. The first network element of  claim 1 , wherein the response to the context request message is from the second network element. 
     
     
       14. The method of  claim 9 , wherein the first and second network elements are network elements of a core network. 
     
     
       15. A first network element capable of offloading user plane traffic, the first network element comprising:
 a memory; and 
 at least one processor coupled to the memory and configured to:
 receive a first message comprising a first NAS request message that is received from a UE; 
 send a context request message to a second network element, wherein the first network element is different from each of the second network element and the UE; 
 receive a response to the context request message, the response including information for one or more Packet Data Network (PDN) connections, the response including one or more indicators associated with at least one of the one or more PDN connections; 
 determining whether the one or more indicators in the response to the context request message include an identifier of a third network element that is part of a local network; 
 in response to determining that the one or more indicators in the response to the context request message include the identifier of the third network element, sending a second message to the UE, wherein the second message is at least one of (a) a response to the first NAS request message or a second NAS request message or (b) a third message associated with performing a Detach Procedure initiated by the first network element; and 
 in response to determining that the one or more indicators in the response to the context request message does not include the identifier of the third network element, determine that dedicated bearers or a secondary Packet Data Protocol (PDP) context for user plane traffic routed to a local gateway are not supported, 
 
 wherein the one or more PDN connections are activated subsequent to receiving a request from a fourth network element that is part of a local network, and wherein the request from the fourth network element comprises another NAS message from the UE and one or more second indicators. 
 
     
     
       16. The first network element of  claim 1 , wherein determining that the dedicated bearers or the secondary PDP context for the user plane traffic routed to the local gateway are not supported comprises rejecting a request for one of the dedicated bearers or the secondary PDP context, wherein the request for the one of the dedicated bearers or the secondary PDP context comprises a request for bearer resources linked to the at least one of the one or more PDN connections. 
     
     
       17. The first network element of  claim 16 , wherein rejecting the request for one of the dedicated bearers or the secondary PDP context comprises sending a message with a cause value, wherein the cause value prevents the UE from retrying a request for one of the dedicated bearers or the secondary PDP context. 
     
     
       18. The method of  claim 9 , wherein determining that the dedicated bearers or the secondary PDP context for the user plane traffic routed to the local gateway are not supported comprises rejecting a request for one of the dedicated bearers or the secondary PDP context, wherein the request for the one of the dedicated bearers or the secondary PDP context comprises a request for bearer resources linked to the at least one of the one or more PDN connections. 
     
     
       19. The method of  claim 18 , wherein rejecting the request for one of the dedicated bearers or the secondary PDP context comprises sending a message with a cause value, wherein the cause value prevents the UE from retrying a request for one of the dedicated bearers or the secondary PDP context.