The standard connectors were deliberately intended to enforce the directed topology of a USB network: Type-A receptacles on host devices that supply power and Type-B receptacles on target devices that draw power. This prevents users from accidentally connecting two USB power supplies to each other, which could lead to short circuits and dangerously high currents, circuit failures, or even fire. USB does not support cyclic networks and the standard connectors from incompatible USB devices are themselves incompatible. COUNT 4
QSN1 What do Type-A receptacles do on host devices? ANS1 supply power QSN2 What do Type-b receptacles do on target devices? ANS2 draw power QSN3 What do the receptacles prevent user from doing? ANS3 from accidentally connecting two USB power supplies to each other QSN4 What networks do USB not support? ANS4 cyclic networks