You want to restrict the OData call on collection Endpoint.
- SAP Cloud for Customer
- SAP Business ByDesign
Generally, a restriction to access an EntitySet without filter options is not allowed as per the OData protocol.
OData, Restriction , KBA , AP-RC-ODF , OData framework (C4C Only) , AP-RC-ODF-BYD , OData Framework and Console (ByD) , Problem