Techniques for detecting duplicate data flows. A data packet of a data flow is received by computer hardware the data packet having a first five tuple, an ingress interface and a VLAN tag. Data is sent to a central processing unit. The central processing unit installs policy tiles into a policy tile database of the computer hardware, the policy tiles including the first five tuple, the first ingress interface and the first VLAN tag. A second data packet is received and compared with the policy tiles in the policy tile database. If the second data packet has the same five tuple as the first data packet but has either a different ingress interface or a different VLAN tag, then the second data packet is determined to be a duplicate of the first data flow and is dropped.