A system for securely transmitting an information package (10) to an addressee via a network (108) includes a directory interface (110) adapted to check a directory (112) to determine whether the addressee has a public key; an escrow key manager (116), coupled to the directory interface (110), adapted...http://www.google.com.tw/patents/US7171000?utm_source=gb-gplus-share專利 US7171000 - Simplified addressing for private communications
