Patent ID: 9002357
Filing Date: 2015-04-07
Classification: H04L,H04W

Abstract:
1. A method to facilitate handover security, the method comprising: deriving a key value using a key derivation function (KDF) for handover from a Global System for Mobile Communications Enhanced Data rates for GSM Evolution Radio Access Network/Universal Terrestrial Radio Access Network (“GERAN/UTRAN”) to an Evolved Universal Terrestrial Radio Access Network (“E-UTRAN”) system using a first input value; performing the handover using the key value derived using the first input value; and deriving a key value using the KDF for a connection establishment using a second input value, wherein the first input value is different from the second input value and is different from input values derived subsequent to the second input value, and establishing the connection using the key value derived using the second input value; wherein the first input value, the second input value and the input values derived subsequent to the second input value are input to a same key derivation function that outputs a key for use between a network entity and user equipment during the handover and connection establishment; and wherein the first input value and the second input value are indicative of uplink non-access stratum count values, the second input value and the input values derived subsequent to the second input value are values within a range of [0,2