Method and arrangement in a telecommunication system

摘要

The invention relates to a method and arrangement in a serving Radio Network Controller, SRNC for controlling inter RAT handover to E-UTRAN of a UE with E-UTRA capability operating in a serving network comprising said SRNC, wherein the SRNC receives, from a Serving GPRS Support Node, SGSN, security keys generated at authentication and key agreement, AKA, upon attachment of the UE to the serving network; characterized in the steps of—determining (202) which type of UICC the UE is equipped with by analyzing the security keys received from SGSN; —using the knowledge of which type of UICC the UE is equipped with to base a decision (204) on whether to allow handover of the UE to E-UTRAN.

主权项

1. A method in a serving Radio Network Controller (SRNC), comprising:
controlling an inter Radio Access Technology (RAT) handover to Evolved Universal Terrestrial Access Network (E-UTRAN) of a User Equipment (UE) with Evolved Universal Terrestrial Access (E-UTRA) capability operating in a serving network comprising said SRNC, wherein the SRNC receives, from a Serving GPRS Support Node (SGSN), security keys generated at Authentication and Key Agreement (AKA) upon attachment of the UE to the serving network, wherein the controlling includes:
determining which subscription that is provided to the UE by a UMTS Integrated Circuit Card (UICC)that the UE is equipped with by analyzing the security keys received from SGSN; andusing the knowledge of which subscription that is provided to the UE by the UICC that the UE is equipped with to base a decision on whether to allow handover of the UE to E-UTRAN,wherein the step of determining which subscription that is provided to the UE by the UICC that the UE is equipped with comprises:
checking when a ciphering key (CK) received from SGSN consist of two identical 64 bit ciphering keys (Kc) in accordance with the function CK=Kc∥Kc, andwhen not, concluding that the UE is equipped with a UICC that provides a UMTS subscription; otherwise,calculating a test value in accordance with the function IK=Kc1 xor Kc2∥Kc∥Kc1 xor Kc2, where Kc=Kc1∥Kc2 is one of the two identical 64-bit Kc and Kc1 and Kc2 are both 32 bits long, such that if the test value equals IK received from SGSN, then concluding that the UE is is equipped with a UICC that provides a GSM subscription, otherwise, concluding that the UE is equipped with a UICC that provides a UMTS subscription.