A keyboard equipped with switching interfaces includes a key set module, a circuit unit, a wired transmission interface, a wireless transmission interface and a switch unit. The latch mechanism includes a bracket adapted to be attached to the first member and bolt pivotally coupled to the bracket. The private key is updated at group level on each revocation within the group and at member level only on anonymous signing of a message by the member. Temperature variation can be optimized to be less than 2% over the temperature range 40 C to 85 C.