Packet Order Correction (POC) is one technique for minimizing packet loss, another is Forward Error Correction (FEC). While forward error correction works with reconstruction data, the method for determining the correct packet order starts at the edge devices of the wide area networks
.With Packet Order Correction, the data packets are marked before they are transmitted over a WAN link. With this marking by means of tagging, each data packet is assigned a number that ensures that the data packets can be put in the correct order after they are received. This method can be used to coordinate data packets that do not arrive in the correct order. Packet Order Correction can be handled by routers or separate appliances in real time. To ensure that even long packet sequences can be correctly coordinated, the devices are equipped with correspondingly large caches.