An optical data network (or ODN) was a system of fiber optic cables on board starships and space stations that was used for data transfer between computers and remote terminals. There were large bundles of optical cables connecting the redundant computer cores. In 2369, Miles O'Brien had not been able to find ODN access on Deep Space 9 by the time Benjamin Sisko arrived several days after him. (DS9: "Emissary") In 2371, Commander Chakotay reported that the nucleogenic cloud being knocked out the USS Voyager's optical data network. (VOY: "The Cloud")