本文介紹了串空間模型中的基本概念和定理，并首次利用串空間理論，從機密性和認證性兩個方面，對改進的NSSK 協議[1]進行了分析。分析結果表明改進的NSSK 協議是
安全的。
關鍵詞：安全協議;串空間;NSSK 協議

The Strand Space Model of NSSK Protocol and Its Analysis ZHOU Qing-lei1,2 , WANG Feng2 , ZHAO Dong-ming2 ( 1. School of Information Engineering ,PLA Information Engineering University ,Zhengzhou Henan China 450000 ; 2. School of Information Engineering , Zhengzhou University ,Zhengzhou Henan China 450052) Abstract: The basic notion and theorems of strand spaces model are introduced. It is the first time to prove the modified version of NSSK protocol with strand space theory from the aspects of both confidentiality and authentication . The analysis proved the correctness of the modified
NSSK protocol.
Key words: Security Protocol ; Strand Space ; NSSK Protocol