Patent ID: 8886935
Filing Date: 2014-11-11
Classification: H04L,H04W,Y04S

Abstract:
1. A rekey method for a communication device, comprising: configuring a microprocessor to provide a key control mechanism to derive two or more purpose specific key array from one master key where the purpose specific key in each of the derived purpose specific key array are cryptographically independent of each other; using one of the two or more purpose specific key array for one of the two or more specific purposes in an application and using other one of the two or more purpose specific key array for other one of the two or more specific purposes in said same application in such a way so that each of the two or more specific purposes in said same application uses different purpose specific key array; and using one purpose specific key array for an application that has only one specific purpose, wherein only one purpose specific key in the key array is effective at same time, and when an effective purpose specific key need to rekey, the key control mechanism stores an array index value corresponding to the effective purpose specific key as used and uses one of unused purpose specific key from the key array as new effective purpose specific key.