 In later implementations of Token Ring, Cat 4 cabling was also supported, so 8P8C ("RJ45") connectors were used on both of the MAUs, CAUs and NICs; with many of the network cards supporting both 8P8C and DE-9 for backwards compatibility.When no station is sending a frame, a special token frame circles the loop.This special token frame is repeated from station to station until arriving at a station that needs to send data.