Apparatus, systems, and methods may operate to provide, to a memory device, an obfuscated clear-page address derived from a clear-page address that is not the same as a key-page address and/or providing, to the memory device, an obfuscated key-page address derived from the key-page address when the obfuscated clear-page address is the same as the key-page address. Additional apparatus, systems, and methods are disclosed.