Abstract: The security mechanism protects the SQlite database and is based on the client/server model. As for the client, the security mechanism not only fulfils the encryption and decryption interface functions with Blowfish, but also builds a local server. With regard to the server, the security mechanism provides key service for the client, lossreport service, and identification service.

Key words: Android； SQlite； Blowfish； encryption； remote service