Good single sign-on solution for Laravel [closed]
You can use the SAML standard in order to solve your SSO needs.
Review this github repository that help you implement a SAML service provider:https://github.com/aacotroneo/laravel-saml2
If you need to implement a SAML Identity provider you can use simpleSAMLphp and use Lavarel database as authentication source.https://simplesamlphp.org/docs/stable/simplesamlphp-idp
You can try out the miniorange/saml-laravel-free package. It makes things quite simple as it also provides a GUI and also does the whole authentication thing own its own.