def notificationNch():
    """NOTIFICATION/NCH Section 9.1.21b"""
    a = L2PseudoLength(l2pLength=0x01)
    b = TpPd(pd=0x6)
    c = MessageType(mesType=0x20)  # 00100000
    d = NtNRestOctets()
    packet = a / b / c / d
    return packet