Using Quorum Blockchain Service (QBS), you can create private consortium blockchain networks, or consortiums, where each blockchain network is limited to specific participants in the network. Only participants in the consortium can view and interact with the blockchain.
Consortiums in QBS can contain two types of member participant roles: administrators and users. Consortiums can be a mix of participant roles and can have an arbitrary number of each role type. There must be at least one administrator.
Taking consortium management actions, such as adding or removing participants in your consortium, currently requires ConsenSys to do this for you. You can request this by submitting a support ticket.
Self-service capabilities for consortium management will be coming soon through the QBS management API.