Method and apparatus for reducing signaling in a core network
The disclosure relates to a method and apparatus in telecommunications, and particularly to reducing signaling in a core network involved in changes of states of a wireless terminal ( 4 ). According to the disclosure a reduced context is allocated based on parameters received by a base station ( 2 ). The reduced context is used by the base station for reconfiguring a RRC connection between the wireless terminal ( 4 ) and the base station ( 2 ) by means of the reduced context, such that the signaling is hidden from a Serving GateWay, SGW ( 10 ).
1. A method performed by an evolved Node B, eNB, for reducing signaling in a Core Network, CN, relating to state changes in a User Equipment, UE, said eNB having a Radio Resource Control, RRC, connection with the UE, the method comprising,
sending a request for a UE context release to a Mobile Management Entity, MME, in response to that the UE has been inactive during a predetermined time,
receiving from the MME, a command for a UE context release together with parameters for enabling local eNB paging of the UE,
releasing the RRC connection,
allocating a reduced context based on the received parameters and storing the reduced context in a memory of the eNB,
retrieving the stored reduced context after receiving a downlink packet to the UE and after receiving a service request from the UE requesting that the UE return to a connected state,
reconfiguring the RRC connection by means of the reduced context, such that the signaling is hidden from a Serving GateWay, SGW, of the CN, and
paging the UE locally by means of the reduced context.
2. The method according to claim 1 , further comprising
starting a timer when storing the reduced context and upon timing out thereof,
releasing the stored reduced context.
3. The method according to claim 1 , further comprising
monitoring memory resources in the eNB and upon detection that a predetermined amount of the memory resources are occupied,
releasing the reduced context.
4. The method according to claim 1 , wherein the reduced context comprises a System architecture evolution Temporary Mobile Station Identity, S-TMSI, an International Mobile Subscriber Identity, IMSI mod 1024 and/or a UE specific Discontinuous Reception, DRX.
5. The method according to claim 1 , wherein the reduced context comprises bearer and security configuration parameters.
6. The method according to claim 1 , further comprising allocating a key comprising a DownLink Internet Protocol address, DL IP@, and a Tunnel End point IDentifier, TEID on S1-U for identifying the reduced context when a downlink packet associated with the reduced context arrives.
7. The method according to claim 1 , wherein the reduced context is a partial UE context enabling the reconfiguring of the RRC connection between the UE and the eNB without signaling with the SGW.
8. The method according to claim 1 , wherein the reduced context is a mini MME context enabling the eNB to handle a service request from the UE without signaling with the MME.
9. An evolved Node B, eNB, for reducing signaling in a Core Network, CN, relating to state changes in a User Equipment, UE, said eNB being configured to have Radio Resource Control, RRC, connections with the UEs, said eNB comprising:
a communications interface (IF), via which, the eNB is connectable to the UE and a Mobile Management Entity, MME, a processor, and a computer readable medium storing computer program code which, when run in the processor, causes the eNB to:
send a request for a UE context release to a Mobile Management Entity, MME, in response to that the UE has been inactive during a predetermined time,
receive, from the MME, a command for a UE context release together with parameters for enabling local eNB paging of the UE,
release the RRC connection,
allocate a reduced context based on the received parameters and storing the reduced context in a memory of the eNB,
retrieve the stored reduced context after receiving a downlink packet to the UE and after receiving a service request from the UE requesting that the UE return to a connected state,
reconfigure the RRC connection by means of the reduced context, such that the signaling is hidden from a Serving GateWay, SGW, of the CN, and
page the UE locally by means of the reduced context.
10. The eNB according to claim 9 , which further is caused to:
start a timer when the reduced context is stored and upon timing out thereof,
release the stored reduced context.
11. The eNB according to claim 9 , which is further caused to:
monitor memory resources in the eNB and upon detection that a predetermined amount of the memory resources are occupied,
release the reduced context.
12. The eNB according to claim 9 wherein the reduced context comprises a System architecture evolution Temporary Mobile Station Identity, S-TMSI, an International Mobile Subscriber Identity, IMSI mod 1024 and/or a UE specific Discontinuous Reception, DRX.
13. The eNB according to claim 9 , wherein the reduced context comprises bearer and security configuration parameters.
14. The eNB according to claim 9 , which is further caused to allocate a key comprising a DownLink Internet Protocol address, DL IP@, and a Tunnel End point IDentifier, TEID on S1-U for identifying the reduced context when a downlink packet associated with the reduced context arrives.
15. The eNB according to claim 9 , wherein the reduced context is a partial UE context usable to cause the eNB to reconfigure the RRC connection between the UE and the eNB without signaling with the SGW.
16. The eNB according to claim 9 , wherein the reduced context is a mini MME context usable to cause the eNB to handle a service request from the UE such that the signaling is hidden both from the MME and the SGW.