In a previous post, I described the different types of Data Formats that are commonly used with ESBs, XML Gateways, and SOA. Converting from one format to another is a common task performed by an ESB or XML Gateway. One can make arguments either way about whether this functionality should exist in the ESB only or in the ESB and XML Gateway. From a purist perspective, it can be argued that it should only be done at the ESB tier. From a flexibility perspective, should be able to apply Data Transformations. That being said, I would recommend that only simple (XML->XML transformations accomplished with a XSLT stylesheets be applied to messages at the XML Gateway tier).
Any popular SOA product will provide the ability to apply numerous different types of Data Transformations.
WebSphere DataPower provides support for conversion between all of the data formats mentioned in the Data Formats post-plus, more. DataPower’s original purpose was to provide efficient XML<->XML transformations via XSLT stylesheets.