Method and terminal for determining handover for traffic offloaded onto WLAN

Abstract

There is provided a method for determining a handover. The method may comprise: determining, by User Equipment (UE), whether a timer is running, wherein the UE has accessed multiple Radio Access Technologies (RATs); if the timer is not running, performing, by the UE, a handover of a data traffic, which has been routed onto a Wireless LAN (WLAN), to an original RAT; and if the timer is running, not performing, by the UE, the handover of the data traffic, which has been routed onto the WLAN, to the original RAT. The data traffic may be been routed onto the WLAN as a result of Circuit Switched Fall-Back (CSFB) or 3GPP RAT mobility.

The invention claimed is: 
     
       1. A method for offloading non-voice traffic, the method comprising:
 receiving, at a user equipment (UE) connected to an E-UTRAN, a Circuit Switched (CS) Service Notification from an eNodeB, wherein the UE supports Multi-Access Packet Data Network Connectivity (MAPCON) and Internet Protocol Flow Mobility and Seamless Offload (IFOM), and wherein an Inter System Routing Policy (ISRP) is stored in the UE; 
 connecting to a UTRAN as a result of a handover procedure triggered by the CS Service Notification; 
 offloading non-voice traffic to a WLAN based on the ISRP while connecting to the UTRAN; 
 connectingre-connecting to anthe E-UTRAN as a result of a handover procedure; 
 re-routing the non-voice traffic through the E-UTRAN after re-connecting to the E-UTRAN if it is determined that a timer has expired; and 
 maintaining the offloading of the non-voice traffic through the WLAN after re-connecting to the E-UTRAN if it is determined that the timer has not expired. 
 
     
     
       2. The method of  claim 1 ,
 wherein the non-voice traffic is re-routed through the E-UTRAN if it is determined that the timer has expired and it is determined that a marker for the non-voice traffic is removed; and wherein the offloading of the non-voice traffic through the WLAN is maintained if it is determined that the timer has not expired and the marker for the non-voice traffic is not removed. 
 
     
     
       3. The method of  claim 1 , wherein the offloading of the non-voice traffic to the WLAN is based on the ISRP and in accordance with Circuit Switched Fall-Back. 
     
     
       4. The method of  claim 1  further comprising:
 receiving the ISRP from an Access Network Discovery and Selection Function (ANDSF). 
 
     
     
       5. The method of  claim 1  further comprising:
 selecting an access technology or an access network, or both, for routing non-voice traffic matching specific IP flows identified in the ISRP when the UE is using Internet Protocol Flow Mobility and Seamless Offload (IFOM). 
 
     
     
       6. The method of  claim 1  further comprising:
 selecting an access technology or an access network, or both, for routing non-voice traffic matching a specific Access Point Name (APN) identified in the ISRP when the UE is using Multi-Access Packet Data Network Connectivity (MAPCON). 
 
     
     
       7. A User Equipment (UE) for offloading non-voice traffic, the UE comprising:
 a transceiver unit that receives a Circuit Switched (CS) Service Notification from an eNodeB while the UE is connected to an E-UTRAN, wherein the UE supports Multi-Access Packet Data Network Connectivity (MAPCON) and Internet Protocol Flow Mobility and Seamless Offload (IFOM), and 
 wherein an Inter System Routing Policy (ISRP) is stored in the UE; and a control unit processor that causes the UE to: 
 connect to a UTRAN as a result of a handover procedure triggered by the CS Service Notification; 
 offload non-voice traffic to a WLAN based on the ISRP while connecting to the UTRAN; 
 connectre-connect to anthe E-UTRAN as a result of a handover procedure; 
 re-rout the non-voice traffic through the E-UTRAN if it is determined that a timer has expired after re-connecting to the E-UTRAN; and 
 maintain the offloading of the non-voice traffic through the WLAN after re-connecting to the E-UTRAN if it is determined that the timer has not expired. 
 
     
     
       8. The UE of  claim 7 , wherein the control unit processor further causes the UE to:
 re-rout the non-voice traffic through the E-UTRAN if it is determined that the timer has expired and it is determined that a marker for the non-voice traffic is removed; and maintain the offloading of the non-voice traffic through the WLAN if it is determined that the timer has not expired and the marker for the non-voice traffic is not removed. 
 
     
     
       9. The UE of  claim 7 , wherein the control unit processor further causes the UE to offload the non-voice traffic to the WLAN based on the ISRP and in accordance with Circuit Switched Fall-Back. 
     
     
       10. The UE of  claim 9 , wherein the ISRP is received from a node that is responsible for an Access Network Discovery and Selection Function (ANDSF). 
     
     
       11. The UE of  claim 7 , wherein the control unit processor selects an access technology or an access network, or both, for routing non-voice traffic matching specific IP flows identified in the ISRP when the UE is using Internet Protocol Flow Mobility and Seamless Offload (IFOM). 
     
     
       12. The method of  claim 7 , wherein the control unit processor selects an access technology or an access network, or both, for routing non-voice traffic matching a specific Access Point Name (APN) identified in the ISRP when the UE is using Multi-Access Packet Data Network Connectivity (MAPCON).