Abstract: A delivery system uses secure containers each equipped with means such as a keypad (8) or barcode reader (10) to input a single use delivery key. The delivery key is generated by an external code generator that produces pseudo noise codes. A generator (20) that produces the same sequence is provided in the lock and synchronization between the two generators is provided by the delivered items.
Abstract: A secure container (2) has a combination lock (6) that is always operable in response to at least one master key and is also operable on a single occasion in response to a transaction-unique delivery key generated from the master key. The lock (6) also contains processor means (20) for comparing or decoding the delivery key, means (10, 20, 26) for releasing the lock in response to a valid delivery key, and storage means (22) for identifying used delivery keys.