An identity is communicated by a client device to a server without requiring the identity to be disclosed to eavesdroppers and without requiring the use of symmetric or asymmetric cryptography. A servo loop generates a position error signal to control the position of the head. An angular crimping technique where piercing members are driven through framing members in at least two different directions to crimp the framing members together. A hood is pivotally mounted over the door and mount opening, and is operable for displacement with respect to the mount when engaged by the door andor by fluid flowing through the discharge conduit.