Hi, I'm working on the REST service and desktop application. I'm thinking about authentication. My app will be for small companies. I assume that one client will have 1-5 users. My first thought was "let's use Azure AD B2B", but after few hours of research I have doubts if this would be good approach. Those companies in 90% would not have own Azure AD, and creating on my own for them domain for one user would be over-engineering.
So, what is an optimal way to implement multi-tenant authentication using trusted services. I would like to avoid using hand made authentication, because of security concerns. Maybe someone done similar using standard Azure AD (no B2B)?