Streaming-based Processing of Secured XML Documents

WS-Security is a standard providing message-level security in Web Services. It allows exible application of security mechanisms in SOAP messages. Therewith it ensures their integrity, con dentiality and authenticity. However, using sophisticated security algorithms can lead to high memory consumptions and long evaluation times. In the combination with the standard XML DOM processing approach the Web Services servers become a simple target of Denial-of-Service attacks. This thesis presents a solution for these problems an external streaming-based WS-Security Gateway. First the di culties and limitations of the streaming-based approach applied on secured XML documents are discussed. Then the implementation of the WS-Security Gateway is presented. The implementation is capable of processing XML signatures in SOAP messages. The evaluation shows that streaming-based approach enhances the performance and is much more e cient in comparison to standard DOM-based frameworks. It is also proved that the implementation is under certain circumstances resistant against signature wrapping attacks.