Message Transmission Optimization Mechanism or shortly MTOM (a W3C standard) is a way to efficiently send binary data to and from web services.
It uses XML binary Optimized Packaging (XOP) to transfer binary data and is intended to replace both MIME and DIME attachments.
Binary files are usually seen as a sequence of bytes (groups of eight binary digits or bits). Binary files typically contain bytes that do not have to be interpreted as text characters, but should be different. In a SOAP message, however, such a so-called array or bytes is often encoded as text data. MTOM makes it possible to place the binary data of large files more effectively in a SOAP request (request) or response (response). Also see
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