I am learning about SAML and already read many articles and forums but I still having confusion about setup IdP. I am using "https://simplesamlphp.org/"
For example, I have 3 websites "example.com", "one.example.com", "two.example.com"; All are on three different server. Now, I want to setup single sign on login using SAML then on which server I need to setup IdP. As "example.com" is main domain which has all the information about user.
As I learn, when I login to "example.com" then it sends request to IdP.
But I don't get any idea where I have to set IdP and what Idp contains?. Its on same server where "example.com" hosted OR its different server and what logic I have to write on that server? It's simple login function OR I need to setup "simplesaml" for this and set login logic to there.
After setting up IdP, what I need to do on other server "one.example.com", "two.example.com"? Do I need to install again "simplesaml" to both server and set SP and IdP?
In sort, which server has IdP and SP? And on which server I need to install "simplesaml"?
Thanks in advance