An industrial automation module (14, 16, 18, 60, 100, 202, 204, 208, 504, 506, 604, 606) for an industrial control system comprising: an enclosure providing left (61, 102) and right (62, 104) flanking sides; releasable electrical connectors (64, 106, 108, 209, 211) supported on the left and right flanking sides exposed to connect adjacent industrial automation modules on the left and right sides; a plurality of electrical terminals (70, 120) for receiving conductors exposed on a surface of the enclosure to releasably retain electrical conductors communicating with an I/O function card (290, 292) held within the enclosure; backplane circuitry held within the enclosure and communicating with the releasable electrical connectors to establish a ring network communicating among attached base modules to provide a first port at one electrical connector and a second port at the second electrical connector so that the base modules may be arranged in a ring wherein the first and second ports of each base module couple to a different base module of the ring; and a switching node (362, 412, 432) being embedded in the I/O function card, wherein the releasable electrical connectors are configured to provide data to the switching node, and wherein the switching node is an active ring supervisor adapted to operate to: (a) transmit beacon frames out of each port at a first rate and monitor the other port for reception of beacon frames, wherein the beacon frames indicate a state of operation of the ring network as a closed mode or an open mode; (b) respond to a receipt of beacon frames between the first and second ports by blocking data frames between the first and second ports in an open mode; (c) respond to failure of the beacon frames to traverse the ring by changing to a closed mode passing data frames between the first and second ports. an enclosure providing left (61, 102) and right (62, 104) flanking sides; releasable electrical connectors (64, 106, 108, 209, 211) supported on the left and right flanking sides exposed to connect adjacent industrial automation modules on the left and right sides; a plurality of electrical terminals (70, 120) for receiving conductors exposed on a surface of the enclosure to releasably retain electrical conductors communicating with an I/O function card (290, 292) held within the enclosure; backplane circuitry held within the enclosure and communicating with the releasable electrical connectors to establish a ring network communicating among attached base modules to provide a first port at one electrical connector and a second port at the second electrical connector so that the base modules may be arranged in a ring wherein the first and second ports of each base module couple to a different base module of the ring; and a switching node (362, 412, 432) being embedded in the I/O function card, wherein the releasable electrical connectors are configured to provide data to the switching node, and wherein the switching node is an active ring supervisor adapted to operate to: (a) transmit beacon frames out of each port at a first rate and monitor the other port for reception of beacon frames, wherein the beacon frames indicate a state of operation of the ring network as a closed mode or an open mode; (b) respond to a receipt of beacon frames between the first and second ports by blocking data frames between the first and second ports in an open mode; (c) respond to failure of the beacon frames to traverse the ring by changing to a closed mode passing data frames between the first and second ports. (a) transmit beacon frames out of each port at a first rate and monitor the other port for reception of beacon frames, wherein the beacon frames indicate a state of operation of the ring network as a closed mode or an open mode; (b) respond to a receipt of beacon frames between the first and second ports by blocking data frames between the first and second ports in an open mode; (c) respond to failure of the beacon frames to traverse the ring by changing to a closed mode passing data frames between the first and second ports.