In recent years, Web services have been drawing more attention to the computer industry. They are built on open standards and provide solutions for integrating applications across enterprises. The technologies behind Web services are Universal Description, Discovery and Integration, Web Services Description Language and Simple Object Access Protocol (SOAP). SOAP, which is responsible for delivering messages between applications, is a connectionless protocol. In other words, SOAP cannot keep the session state between SOAP calls. However, most Ecommerce applications need to maintain...