function putAuthAttributes()
    {
        if (isset($this->username)) {
            $this->putAttribute(RADIUS_USER_NAME, $this->username);
        }
        if (isset($this->response) || isset($this->lmResponse)) {
            $lmResp = isset($this->lmResponse) ? $this->lmResponse : str_repeat ("\0", 24);
            $ntResp = isset($this->response)   ? $this->response :   str_repeat ("\0", 24);
            $resp = pack('CC', $this->chapid, $this->flags) . $lmResp . $ntResp;
            $this->putVendorAttribute(RADIUS_VENDOR_MICROSOFT, RADIUS_MICROSOFT_MS_CHAP_RESPONSE, $resp);
        }
        if (isset($this->challenge)) {
            $this->putVendorAttribute(RADIUS_VENDOR_MICROSOFT, RADIUS_MICROSOFT_MS_CHAP_CHALLENGE, $this->challenge);
        }
    }