This document provides standards necessary to achieve interchangeability between equipment providers. Attachment 1 specifies an interconnection scheme by which aircraft can be wired to enable full interchangeability between OMTS products from different suppliers. Attachment 1 also specifies a minimum interface configuration which can be viewed as a desirable future implementation on new aircraft because of its potential for significant weight and space savings along with the possibility for less complex integration into the OEM production environment. The OMTS standard includes the physical interfaces, wiring, connectors, space envelopes, equipment chassis, unit co-location requirements, and power requirements. The basic functionality within each component of the OMTS is covered. Detailed functionality, protocols, and design parameters unique to each system supplier are not covered in this document. Design guidelines are included that impact the interfaces and installation of cabin equipment on board the aircraft.