OSPF OSPF Cost cost = reference bandwidth / configured bandwidth of interface in kbps reference bandwidth = 100,000 kbps Interface speed OSPF Cost 100 Mbps 1 10 Mbps 10 6 Mbps 17 5 Mbps 20 4 Mbps 25 3 Mbps 33 2 Mbps 50 1.5 Mbps 67 1 Mbps 100 768 Kbps 130 512 Kbps 195 384 Kbps 260 256 Kbps 391 128 Kbps 781 64 Kbps 1563