An apparatus for and method of encapsulating Ethernet frame data in HDLC frames for transmission over a VDSL transport facility. The ball bearing includes inner sections of the seal rings which overlap the end surfaces in an axial direction of the inner ring such that the width of the overlap in the axial direction is 30% or more than the diameter of the balls. The transmitter circuitry sends data to a receiver circuitry in another IC, and the receiver circuitry receives data from a transmitter circuitry in another IC.