Security is a difficult area to say something very specific about - but I would also be concerned to have SDI connected directly to the public internet.
But you could probably put a proxy upfront (ISVA or Apache/IBM HTTPServer) to ensure only validated traffic is coming across. But again this basically is against the beauty of SDI and will basically point to build a "real" web server solution.
I have played around with the SDI HTTP Server connector and it is funny thing to work with and very useful for building SDI functionality - that said I would recommend keeping it away from any uncontrolled domain - also simply because the way it works it is easy to make some stupid error in authentication/aythorization as you code that yourself....
But SDI is IMHO the best integration tool I ever worked with and I love tinkering around with it - so happy SDIing ;-)
HTH
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Franz Wolfhagen
WW IAM Solution Engineer - Certified Consulting IT Specialist
IBM Security Expert Labs
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