A method implemented in a network element, the method comprising identifying a first service function (SF) for validation, the first SF being associated with a service function chain (SFC), being applied to a data flow, and operating on a first network node, encoding one or more tests associated with the first SF in an operations, administration, and management (OAM) packet, and transmitting a validation request comprising the OAM packet towards the first SF to request validation of the first SF by execution of the tests.