Mode of Operation

An algorithm for the cryptographic transformation of data that features a symmetric key block cipher algorithm.
SOURCE: SP 800-38C

Description of the conditions under which an information system operates based on the sensitivity of information processed and the clearance levels, formal access approvals, and need-to-know of its users. Four modes of operation are authorized for processing or transmitting information: dedicated mode, system high mode, compartmented/partitioned mode, and multilevel mode.
SOURCE: CNSSI-4009