In a Time Division Multiple Access communication network, a central office provides interactive communication between a service provider and a plurality of user terminals. The cryptographic module may include a first housing, a user Local Area Network interface carried by the first housing, and a cryptographic processor carried by the first housing and coupled to the user LAN interface. The first step and the second step are repeated. In a further embodiment, an electrode can be formed from a portion of a substrate or well region, and the other electrode can be formed over such portion of the substrate or well region. To provide hydraulic damping and reduced friction, the annular part is provided in the region of the cage guiding face with at least one radial recess outside the rolling body pockets, which can be formed by apertures, cutouts or grooves in the cage guiding face. In another embodiment, the magnet assembly includes a pair of axially magnetized permanent ring magnets also oriented with like poles facing one another.