
Trying to lean salesforce here :)
Thanks
4 answers
Yes, SSP was retired after Spring '12 and Customer Portal replaced it. It does support self-registration — enable it under Setup → Customer Portal → Edit → Self-Registration Activated. You can map self-registered users to a default Role and Profile.
And yes, licenses are required (Customer Portal Enterprise or Manager, depending on access needs). Salesforce later evolved this further into Experience Cloud, which offers even more flexible self-registration and branding options.
If license costs are a concern, third-party portal solutions on AppExchange can be a cost-effective alternative with self-registration built in.