A method begins by a processing module identifying, for a DSN (Dispersed Storage Network) memory using multiple IDA (Information Dispersal Algorithms) configurations simultaneously, a first IDA configuration with a highest security level relative to each of the multiple IDA configurations. The method continues by generating at least one master key. The method continues by encoding the master key with a secure error coding function to produce master key slices according to the first IDA configuration. The method continues by storing the master key slices in the DSN memory using the first IDA configuration. The method continues by, when storing data with a second IDA configuration having a security level lower than the first IDA configuration, retrieving the master key slices, decoding the master key slices to obtain the master key and encrypting the data using the master key.