The content of this book consists of two parts: basic theory part and application field. The theory part introduces the identifier-based CPK Public Key, evidence-based Truth Authentication Logic, the authentication purpose of Information Assurance, the GAP universal authentication protocol, and the core technology of cyber security explored. In application part, new concepts are put forward, such as identifier authentication , "proof before event" ,virtual authentication network which are applied to the communication processes of accessing and receiving, to transaction processes of accepting and adopting, to software processes of downloading (or uploading) and installing (or execution), and to the newly developed products such as digital seal, digital currency, anti-counterfeit labels, asymmetric password and so on. This book is suitable for managers, scholars reading, can be used as a graduate textbook.