[keycloak-user] Help with SSO

Hi, In the past some systems inside my company were using a custom made sso implementation that had the ability to do silent login among them. On of that systems was completly refactored and is using keycloak for authentication and authorization. Since than, we lost that silent login feature with the other systems. We assumed that it was ok to lost this feature for a while but now we are trying to implement the silent login again. So..summing up: - System "A" is using keycloak with a realm "RealmA" with multiple clients (modules) with sso between them. - Other systems "B", "C" with their custom authentication and authorization - We are using a custom federation on keycloak over the same users database that is shared among all the systems. What's the best practise to achieve sso between all the systems? We are thinking about a proxy that detects if the user has a session on some of the other systems and if that is true, we programatically create a session on keycloak for a given (Is this possible with the API?). Thank you, JM