Thanks again for your time Jacob,

Your assumption (a set of data being posted along with an HMAC-SHA1) is correct. The blog you mention is very interesting indeed. I found two T-SQL functions that, when combined, could take care of the SHA1 HMAC and the Base64 encoding. However, there probably are reasons why this is not standard procedure. I found it therefore wiser to take care of both in additional application code behind. The .NET framework makes it easy by making things like the HMACSHA1 Class and the ToBase64String Method available. It was time to take the plunge.

I tried to avoid coding, as the .NET field is new to me. However, you can't just keep on trying to find solutions if these solutions are actualy more time absorbing then the alternative 🙂 It did bring some facts unknown to me to my attention though. Searches like this are never waysted. If an elegant SQL solution comes to my attention, I'll certainly post it here.

As for your questions, I'm using SQL Server 2005 for this. I don't have any influence on the recieving end, as it is an online payment gateway.

Best regards,

- Alex.