This document describes different levels of participation for service providers to join the European Open Science Cloud (EOSC) ecosystem through the EOSC-hub project. It outlines the benefits and requirements for entry, standard, and high levels of participation. The entry level is aimed at any service provider and provides basic benefits like exposure and helpdesk support. The standard level provides additional benefits like integration assistance and input into policies. The high level provides maximum integration and alignment with EOSC-hub service management processes. Authentication and authorization infrastructure solutions and a helpdesk as a service are also described.