Fiber cut in SF area

Peter Beckman beckman at
Mon Apr 13 13:18:54 CDT 2009

On Mon, 13 Apr 2009, Dylan Ebner wrote:

> It will be easier to get more divergence than secure all the manholes in
> the country.

  I still think skipping the securing of manholes and access points in favor
  of active monitoring with offsite access is a better solution.  You can't
  keep people out, especially since these manholes and tunnels are designed
  FOR human access.  But a better job can be done of monitoring and knowing
  what is going on in the tunnels and access points from a remote location.

     Cheap: light sensor + cell phone = knowing exactly when and where the
     amount of light in the tunnel changes.  Detects unauthorized
     intrusions.  Make sure to detect all visible and IR spectrum, should
     someone very determined use night vision and IR lights to disable the

     Mid-Range: Webcam + cell phone = SEEING what is going on plus
     everything above.

     High-end: Webcam + cell phone + wifi or wimax backup both watching the
     entrance and the tunnels.

     James Bond: Lasers.

  Active monitoring of each site makes sure each one is online.

     * Knowing immediately that there is a change in environment in your
     * Knowing who or at least THAT something is in there
     * Being able to proactively mitigate attempts
     * Availability of Arduino, SIM card adapters, and sophisticated sensor
       and camera equipment at low cost

     * Cell provider outage or spectrum blocker removes live notifications
     * False positives are problematic and can lower monitoring thresholds
     * Initial expense of deployment of monitoring systems

  Farmers use tiny embedded devices on their farms to monitor moisture,
  rain, etc. in multiple locations to customize irrigation and to help avoid
  loss of crops.  These devices communicate with themselves, eventually
  getting back to a main listening post which relays the information to the
  farmer's computers.

  Tiny, embedded, networked devices that monitor the environment in the
  tunnels that run our fiber to help avoid loss of critical communications
  services seems to be a good idea.  Cheap, disposable devices that can
  communicate with each other as well as back to some HQ is a way to at
  least know about problems of access before they happen.  No keys to lose,
  no technology keeping people out and causing repair problems.

  Some other things that could detect access problems:
     * Pressure sensors (maybe an open manhole causes a detectable change in
       air pressure in the tunnel)
     * Temperature sensors (placed near access points, detects welding and
       thermite use)
     * Audio monitor (can help determine if an alert is just a rat squealing
       or people talking -- could even be automated to detect certain types of
     * IR (heat) motion detection, as long as giant rats/rodents aren't a problem
     * Humidity sensors (sell the data to weatherbug!)

  One last thought inspired by the guy who posted about pouring quick-set
  concrete in to slow repair.  Get some heavy-duty bags, about 10 feet long
  and large enough to fill the space in the tunnel.  More heavily secure the
  fiber runs directly around the access space, then inflate two bags on
  either side of the access point.  Easily deflated, these devices also have
  an electronic device which can notify HQ that they are being deflated or
  the pressure inside is changing (indicating pushing or manipulation).
  That way you only need to put these bags at access points, not throughout
  the whole tunnel.

  Kinda low-tech, but could be effective.  No keys needed, could be
  inflated/deflated quickly, and you still get notification back to a
  monitoring point.

Peter Beckman                                                  Internet Guy
beckman at                       

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