Abstract:

Network authentication technology is the key to the application of internet plus security. The digital signature which depends on the certificate authority （CA）and PKI based on public key system is the main method for identity and message authentication. However，over the years，there are still many problems for the development of CA. The digital signature is not mutual trust and mutual recognition over the application granted by different CA. Moreover，it costs a lot to construct and maintain CA. In order to solve the above problems，one of ways for the improvement is to shorten the length of public key under the condition of not reducing the degree of security. In this way，the public key can be widely recognized under the regulations instead of the third party certification. The application of this public key technology will be an effective way to remove the existing problems of the CA.

Key words: digital signature, authentication center, visual public key