Efficient Secure Electronic Mail Protocols with Forward Secrecy
In 1976, Diffie and Hellman proposed the concept of public key cryptosystem (PKC). The application and research of public key cryptography are arisen in the modern cryptography. In 2005, Sun, Hsieh, and Hwang (S.H.H.) proposed an electronic mail protocol based on classic public key cryptography. The technique of the Certificate of Encrypted Message Being a Signature (CEMBS) that Bao proposed in 1998 is applied on session key sharing of their e-mail system. In the same year, Dent pointed out that the first one of S.H.H.¡¦s e-mail protocols cannot suffice the property of forward secrecy. Thus, Kim, Koo, and Lee (K.K.L.) proposed two e-mail protocols based on signcryption concept which is proposed by Zheng in 1997 to overcome the flaw of S.H.H.¡¦s e-mail protocol in 2006. Lin, Lin, and Wang (L.L.W.) pointed out that the second one of S.H.H.¡¦s protocols cannot achieve forward secrecy and then they improved the protocol. In 2007, Yoon and Yoo claimed that the second one of K.K.L.¡¦s protocols is still vulnerable to two possible forgery attacks. In this thesis, we will make deep discussions about secure e-mail protocols based on PKC with providing the property of forward secrecy and then build a novel e-mail protocol to withstand the above attacks. Our proposed e-mail protocol can achieve the properties of authentication, confidentiality, integrity, non-repudiation and forward secrecy.
Advisor:Cha-Hwa Lin; Chun-Hung Lin; Chun-I Fan
School:National Sun Yat-Sen University
School Location:China - Taiwan
Source Type:Master's Thesis
Keywords:forward secrecy signcryption authentication electronic mail protocols key agreement public keys
Date of Publication:09/07/2007