A system, comprising: - a network manager device (516; 702; 802; 902) having a first port (544; 713; 815; 915) and a second port (546; 715; 817; 917); - a first client device (528, 530, 532, 534, 536; 704, 706, 708, 710, 712; 804, 806, 808, 810, 812; 904, 906, 908, 910, 912) having a first port and a second port, the first port of the first client device connected to the first port of the network manager device; and - a second client device (528, 530, 532, 534, 536; 704, 706, 708, 710, 712; 804, 806, 808, 810, 812; 904, 906, 908, 910, 912) having a first port and a second port, the first port of the second client device connected to the second port of the first client device and the second port of the second client device connected to the second port of the network manager device; wherein the network manager device, the first client device, and the second client device are part of an Ethernet network (504; 700; 800; 900); wherein the Ethernet network is configured in a ring topology; wherein the network manager device is configured to transmit a frame (600, 600'; 714, 716; 814, 816; 914, 916) having a count field; wherein the first client device is configured to increment a value of the count field once by a predetermined value based on a successful reception of the frame from the network manager device and an ability to communicate with the second client device; wherein the first client device is configured to increment the value of the count field twice by the predetermined value based on a failed transmission to the second client device; wherein the first client device and the second client device are configured so that the frame is received back by the network manager device as a received frame; wherein the network manager device is configured to determine a status of the Ethernet network based on whether the received frame is received on a port of the network manager device from which it was sent or on a port of the network manager device different from the port from which it was sent; wherein the network manager device is configured to determine that the network is open by determining that the received frame was received on the same port of the network manager device from which it was sent; and wherein the network manager device is configured to identify a faulted client device based on the value of the count field. - a network manager device (516; 702; 802; 902) having a first port (544; 713; 815; 915) and a second port (546; 715; 817; 917); - a first client device (528, 530, 532, 534, 536; 704, 706, 708, 710, 712; 804, 806, 808, 810, 812; 904, 906, 908, 910, 912) having a first port and a second port, the first port of the first client device connected to the first port of the network manager device; and - a second client device (528, 530, 532, 534, 536; 704, 706, 708, 710, 712; 804, 806, 808, 810, 812; 904, 906, 908, 910, 912) having a first port and a second port, the first port of the second client device connected to the second port of the first client device and the second port of the second client device connected to the second port of the network manager device; wherein the network manager device, the first client device, and the second client device are part of an Ethernet network (504; 700; 800; 900); wherein the Ethernet network is configured in a ring topology; wherein the network manager device is configured to transmit a frame (600, 600'; 714, 716; 814, 816; 914, 916) having a count field; wherein the first client device is configured to increment a value of the count field once by a predetermined value based on a successful reception of the frame from the network manager device and an ability to communicate with the second client device; wherein the first client device is configured to increment the value of the count field twice by the predetermined value based on a failed transmission to the second client device; wherein the first client device and the second client device are configured so that the frame is received back by the network manager device as a received frame; wherein the network manager device is configured to determine a status of the Ethernet network based on whether the received frame is received on a port of the network manager device from which it was sent or on a port of the network manager device different from the port from which it was sent; wherein the network manager device is configured to determine that the network is open by determining that the received frame was received on the same port of the network manager device from which it was sent; and wherein the network manager device is configured to identify a faulted client device based on the value of the count field.