We are trying to consume the web service exposed by a WCF (.NET) web server by using Perl 5 The service uses Signature and Encryption on to handle the client requests. It would be great that if anyone can help us to resolve the issues we are currently facing. The system uses X.509 certificate authentication for accessing and sending the soap XMLS. They uses a policy to recieve and send soap messages. Regarding the encryption/decryption methods,The built-in mechanism of the .NET framework has been utilised - .NET Framework’s built-in mechanism is used for the generation of a random symmetric-key for the particular session of the web services. This key is then encrypted with the rsa-oaep asymmetric-key algorithm using the public key of the certificate. - The symmetric-key algorithm AES256-CBC is used for encrypting the soap server's data. This algorithm uses the above random symmetric-key which is also sent with the message. - The random symmetric-key is decrypted using the certificate's private key. - .NET Framework’s built-in mechanism is also used for the random generation of the Initialization Vector (IV). Regarding Policy File In theory, WCF should be inter operable with any solid WS-* Specification Implementation. The WS-Security specification for Microsoft's implementation we are using is WS-Security 1.0 Regarding Attachments MTOM attachments are Base64 strings longer than 1024bytes are converted to binary attachments for optimised transmission. These attachments are referenced from the element they replace. Expecting your earliest response.