Abstract: A workflow control security model for security risks that may exist in the process of workflow rules choreography,storage/access and execution control in the workflow customization of collaborative SaaS platform of industrial chains with dominant enterprise as core was proposed based on the digital signature and service instance association．According to the research on the XML digital signature alone with its validating procedure and the strategy on storage and executing models,a digital signature which includes methods of validating the identity of users and is related to business operations,way of storing and arithmetic was proposed．The security model and arithmetic were validated in the customization and execution of the after service of vehicle on the collaborative SaaS platform of industrial chains,showing that it can prevent illegal tampering and transferring of workflow in the process of choreography,storage and execution.

Key words: SaaS platform,Security,Workflow customization,Digital signature