The VMware licensing service is designed to act as a repository that will host the licensing information of all VMware products that are compatible with the PSC. Now that licensing is managed by a separate service, you will no longer have to perform license management on every vCenter Server in your environment. Since every vCenter 6.0 will have a PSC associated to it, license management is no longer dependent on the availability of vCenter. License information is replicated between only those PSCs which are in the same SSO domain.