Elliptic Curve Encryption Algorithm And Its Application In The Instant Messaging System

With the high development ofintemet,information security has gained more and more attention.An important approach.to solving information security is public-key cryptology. Comparing to other public-key cryptosystems suchas RSA and DSA,ECC has many advantages including high security per bit,faster computations and reduces in processing power,storage space and bandwidth.These advantages make ECC ideal for constrained environments such as PDAs,cellular phones and smart cards.Therefore,in this thesis,Elliptic Curve Cryptography is disgnssed here first.Mathematic fundament of ECC is presented,then its principle is disgussed,the Elliptic Curve Diffie-Hellman key exchange algorithm and the Elliptic Curve Digital Signature Algorithm, finally the efficiency and security of ECC is analysed by comparison.Instant Messaging,IM is popular network service providing on-line states,instant switching characters,speech or video etc.multiple media.At present,most of Instant Messaging system only is considered practicality not security at first.Such as Microsoft MSN only considered the security of landing stage.Message of the communication process is transmitted in form of original text.In order to solve the security of instant mssageing,the paper design a data Encryption Scheme of Network Based on AES and ECC according to between client to client and client to server of scurity of Instant Messageing.The Encryption Scheme is realized by java language.