Design And Implementation Of Identity Authentication System Oriented Instant Messaging

In order to implement the function of effective access control and safe communication, identity authentication is playing important role in all kinds of network applications. Constructing an identity authentication system, which adopts the PKI technology and aims at the security demand of IM used in the special application, provides significant theory meaning and some practical value for reinforcing the security of IM.After the study of PKI system and referring to the safety requirement of IM used in the scoring system on the Web, an Identity Authentication System Oriented Instant Messaging (IASOIM) is constructed, which makes use of the technology of data encryption and digital signature. The design target and basic function of the system has been confirmed and the system's whole frame presented.The paper discusses two function modules in detail, including CA and RA. It analyzes the management of certificate generating, using and revocation process. The key technology is implemented, which includes generating CA root certificate, user certificate application, checking and issuing, certificate revocation and CRL issuing, OCSP inquiry and verifying and LDAP directory services.The paper also discusses how to use the certificate to realize identity authentication and data encryption/decryption in the process of login and communication in IM. The two modules, identity authentication and data encryption/decryption, are specifically designed and the significant technology is analyzed.The practical project has shown that the IM security design based on PKI has realized the confidentiality, integrality, imitation prevention and denying resistance of information, provided the dependable third party authentication, boosted up the security of system and possessed pretty practical value.