A schema for formatting metadata returned as representations of web resources defined in the IVOA Support Interfaces specification (VOSI). See http://www.ivoa.net/Documents/latest/VOSI.html. Indicates whether the service is currently available. The instant at which the service last became available. The instant at which the service is next scheduled to become unavailable. The instant at which the service is scheduled to become available again after a period of unavailability. A textual note concerning availability. A listing of capabilities supported by a service A capability supported by the service. A protocol-specific capability is included by specifying a vr:Capability sub-type via an xsi:type attribute on this element.