A method for straightening, constraining, cutting and terminating a multi-stranded, non-parallel cable. To address this, an OLT includes a first distance information storing unit that stores information on the distance to an ONU in association with identification information which identifies the ONU, and by using the distance information stored in the first distance information storing unit, an activation control unit controls activation of the ONUi. The server authenticates the client and stores the client’s user identifier without the corresponding password in a client credential storage area. The PWM device is capable of generating and outputting a PWM signal automatically with the PWM generator according to setting values set in the PWM setting register, even without an interruption by the software. The system analyzes the retrieved fingerprint to evaluate an impact of the event on corresponding deleted data.