DIME, WSE and INDIGO

SOAP messages are not the best way to send large binary files. As the Web Services emerge, people look for Web services to have more and more functionality. Result was the introduction of Web Services Enhancement (WSE) 2.0. The Web Services Enhancements for Microsoft .NET (WSE) supports attaching files to SOAP messages outside the SOAP envelope; these files are not serialized as XML. This can be beneficial when sending large text or binary files because XML serialization is a very costly process and can result in files much larger than the originals. Direct Internet Message Encapsulation (DIME) is a lightweight, binary message format that WSE uses to encapsulate SOAP messages and their attachments in a DIME message.

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