This part of ISO/IEC 18033 specifies ciphers. A block cipher maps blocks of n bits to blocks n bits, under the control of a key of k bits. A total of six different block ciphers are defined.
The algorithms specifled in this part of ISO/IEC 18033 have been assigned object identifiers in accordance with ISO/IEC 9834. The list of assigned object identifiers is given in Annex B. Any changes to the specification of the algorithms resulting in a change of functional behaviour will result in a change of the object identifiers assigned to the algorithm.