Interest in Web services is rapidly increased from their start of use. To exchange information among the application in standard way is the main goal of web services. This communication between the applications is based on SOAP. SOAP (Simple Object Access Protocol) as the basis application of Web services and SOAP messages are closely related to the heterogeneous Web services. Secure transmission of SOAP messages play a vital role for the applicability of Web services. The main challenges to the secure transmission of SOAP messages includes: confidentiality, authentication, integrity, both-party non repudiation and single sign-on.