How to persist my authentication across different apps

Imagine I have the following implementation:
firstApp.mycompany.com (angular 2 +)
secondApp.mycompany.com (angular 2 +)
thirdApp.mycompany.com (angularJs)
myFourthApp.mycompany.com (react or anything else)

How can I have a single login that persists across all of my applications, so when user goes from one sub-domain to another to open a different application they won’t see the login again.

I searched Single-Sign-On but it seems like its an option when you want to use third party authentication providers which is not my case.

Hi @devops4 and thanks for reaching out,

Our documentation on SSO should give you a good start in figuring out how you’d like to go about implementing this between your applications.

This document will go into different protocols that you can use to achieve SSO between your applications and Auth0 does provide many options to help you along the way. However the particular configuration will depend largely on your use-case and what limitations you’re facing such as what will serve as your Identity Provider that will connect your applications.

If you go a bit more in-depth as to what your use-case will be I may be able to point you towards some possible options that could help along the way.

Best Regards,
Colin

I have read that document and I want to use Inbound SSO. The problem with that is your documentation only says you should use connections for that, but not how to use connections. Would you be able to provide more information about that?

Inbound SSO in Auth0 is handled by connections.

I have three apps(angularJs and angular 8) running on three sub-domains and I want to make sure when a user is authenticated for each of those apps then he won’t need to re-authenticate for others.

Please let me know what information you need.

Also, given that cookies are shared across subdomains, is that possible to achieve seemless login with using same auth0 client_id for all of those applications?

Please let me know if you need any other information.