AT&T Microelectronics, BT&D Technologies, Hitachi Ltd and Fujitsu Ltd have agreed to establish international compatible sources of fibre optic transmitter and receiver modules in support of the Sonet and SDH industry standards: Sonet, Synchronous Optical Network, is the standard for fibre optic voice and data communications, allowing seamless communication across transmission equipment from different vendors; SDH, Synchronous Digital Hierarchy, is the equivalent CCITT standard here in Europe; this agreement enables manufacturers to build their equipment from compatible board-level modules, giving the assurance of multiple sourcing and the four parties have agreed to support common product specifications; these include pin-for-pin compatibility, for transmitters and receivers for Sonet OC-1, OC-3 and OC-12 transmission rates; uniformity and compatibility will be achieved by meeting agreed specs for module pin-out, footprint, logic interface, optical performance parameters and power supply; they will also be compatible with the equivalent SDH STM-1 and STM-4 rates.
