Custom Authentication / Login Provider


we are planning to migrate our ticket system to zammad and have the requirement to use the authentication of our existing software (oauth with also for the helpdesk (some kind of single sign on). We provide a software as a service platform for our customers and have the requirement, that they can login to the help desk with the same credentials as for the other system.

What would be the best way to achieve this requirement? After the first analysis of the possibilities in zermmad, there would be the possibility to use OAuth2 or to implement an custom identity provider like the LDAP implementation. Which one would be the better solution?

With best regards,
Richard Liebmann