In Keystone v3 (Grizzly release), the Domains feature encapsulates users and projects into logical entities that can represent accounts, organizations, etc. However, currently there is no capability or mechanism to manage or enforce quotas at the domain level. Assigning or updating values or limits to a domain will allow the cloud administrator to evaluate domain lists and consumption. In order to achieve these capabilities it will be required to implement quota management and quota monitoring for Keystone domains, by which domain usage can be managed and enforced.
The goal is to support quotas at the OpenStack Domain level.