Unordered error-correcting codes and their applications

The authors give efficient constructions for error correcting unordered codes, i.e., codes such that any two codewords are at a certain minimal distance apart and at the same time they are unordered. They present three constructions together with tables that compare their efficiencies. These codes are used for detecting a predetermined number of symmetric errors and for detecting all unidirectional errors. An application to parallel asynchronous communications is included.