Any device which is part of a communications path and serves one or more of the section, line or path terminating functions. (2) Used for an addressable set of equipment, either an OTS End Terminal or an OTS Repeater. The terms ‘OTS’ and ‘system’ are used for a set of network elements that can be addressed through a common communications link (and are connected by a common Optical Service Channel) either by an EMS or a CIT.