A keying system for providing selective interconnection between a receptacle socket and a connector plug terminating an optic fibre, the connector plug adapted for insertion into the receptacle socket. The keying system comprises a raised boss configured to one of a plurality of predefined boss keying...http://www.google.com.au/patents/US7674046?utm_source=gb-gplus-sharePatent US7674046 - Fibre optic connector keying system
