bitsPortImpedance is a read-only value reporting the impedance mode configured for a BITS-OUT port's electrical interface. An administrator checks this to confirm the port's electrical characteristics match the impedance expected by the connected timing equipment (commonly 100 or 120 ohms for T1/E1 clock feeds). For example, connecting a BITS-OUT port to equipment expecting a different impedance than this object reports would produce a poor electrical match and an unreliable timing signal even if all the framing settings are correct.