Abstract: In order to realize the Web services security in the multilevel security and special cipher environment, based on the modification and expansion of WS-Security specification, SOAP multilevel security polices expand protocol and SOAP multilevel security protocol are proposed, and SOAP security model based on the above protocols is designed and implemented. Relying on the use of multilevel cipher services access technology, this model uses security polices to ensure the SOAP multilevel security. Using the model can validate the integrity and availability of above protocols.

Key words: multilevel security, SOAP, WS-Security, XML-Signature, XML-Encryption