Systems, methods and apparatus for facilitating handover security are provided. In some embodiments, the method can include deriving a key value for handover from a GERAN/UTRAN system to an E-UTRAN system using a first input value. The method can also include deriving a key value 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 wherein the first input value, the second input value and the input values derived subsequent to the second input value are configured to be input to a same key derivation function configured to output a key for use between a network entity and user equipment.