Techniques for tagging packets within a network fabric. An authentication device for a network fabric receives a first packet originating from a source device, in transit to a destination device, corresponding to a first network flow. User identification information corresponding to an authenticated user of the source device is inserted into a Network Services Header of the first packet. Embodiments receive a second packet that corresponds to the first network flow at the authentication device, the second packet including service identification information within a Network Services Header of the second packet that identifies a service type of the network flow. Upon receiving a third packet for the first network flow, the authentication device inserts the user identification and the service identification information into a Network Services Header of the third packet.