PERSEC: um middleware para multicriptografia em web services (versão SDN).

Abstract

Web services are a way to share data and should be treated as a solution to interoperability between heterogeneous systems. However, by having a public infrastructure subject to attacks, security concerns have become challenging. To ensure the security of these applications, some security specifications are used to promote the confidentiality and integrity of information, such as the XML Signature and XML Encryption. However, the encryption process performed by the XML encryption specification degrades the performance of Web Services. Nevertheless, this XML security specification has been widely used to ensure the safety message-level (safety end-to-end), Web Services applications. This is justified because if this type of security is not established, SOAP messages, shared between the client application and the Web service, would be exposed from one point to another of communication between applications, revealing unduly confidential data. Considering this background, there was this work a literature review in order to detect scientific evidence that guide the proposal for a new security solution for Web services, message-level, aiming to reduce the degradation impact caused by the encryption process. Accordingly, the main scientific evidence detected to treat the problem in question was the suggestion to use different cryptographic algorithms for encrypting the data of a SOAP message. This hypothesis has been implemented by means of a middleware, based on an XML Schema for structuring data in a SOAP message confidentiality levels so that, in this way, the middleware was able to encrypt each level by a specific cryptographic algorithm - taking into account the robustness of these cryptographic algorithms in terms of safety, i.e., levels lower confidentiality are encrypted using less secure algorithms, while the highest levels of confidentiality are encrypted using safer algorithms (such as the cryptographic algorithms have fees separate computer, if reasoned that this technique would result in better performance in comparison with the usual procedure to apply only a cryptographic algorithm that eventually could be the most expensive computationally to accomplish this task). Therefore, in order to prove the effectiveness of this technique has been proposed an experimental evaluation, based on the main middleware usage scenarios (which allow encrypting the data of a SOAP message via one, two or three cryptographic algorithms), to see if, in fact, the possibility of applying different cryptographic algorithms, to encrypt a SOAP message, would improve the performance of Web Services that implement the security end-to-end. The results obtained with the execution of the experiments showed that the encryption process, as well as the decryption, the experiments using two or three cryptographic algorithms to encrypt a particular SOAP message, had its processing time significantly reduced from experiments only a cryptographic algorithm employed for the same purpose. This finding served to validate the hypothesis supported this work.