Hi, André -
If I may be so bold as to offer you (and others) a few tips:
1. It is very helpful to your audience when posting a question to expand any acronyms which may not be universally recognized, even though you may be intimately familiar with them. I believe "SIAM" stands for "Service Integration and Management"? I had to perform a web search to find out information that could have very easily been included in your question.
2. It's also a nice touch if you provide some details/context in your question. For example, is "SIAM Identity Provider" a software product, a service, a concept, etc.? Are you referring to a particular vendor? Also, can you provide some explanation on what exactly are you needing to accomplish? Are you wanting to know how to utilize some particular REST API(s)?
3. Be a participant. I see you've been a Community member for very nearly a full year. Congratulations! Answering questions from others on occasion helps to build familiarity with other Community members, which should increase their willingness to answer your questions.
4. Finally, please don't utilize larger font point sizes in your posts, as was done here. It's somewhat rude and quite the put-off. Antagonizing your audience is usually not a wise strategy for obtaining good responses.
I hope the Community can help you find some answers to your question.
Best regards, John
I will ask the supplier then.
Thank you.
André