The ABCO Construction Surveillance System

Martin Jordan
Dale R. "Zy" Fox

 

This case is based on Martin Jordan's experience running his own small business.  Martin got involved with computer networks and video surveillance systems from working with his parent's small business.  He has since branched out to work for others.  I am putting the case together, though basically everything is coming from Martin.  Some things have been altered to make sure no one knows all that much about the actual business.

 

Some Background.  ABCO is a fairly small construction company that specializes in building things like garages, decks and additions on homes.  They have a construction yard in Middletown, CT.  This yard is large enough to justify having four surveillance cameras.  They have had things like automobiles disappear from the yard even with the cameras installed!

The cameras have been installed so to maximize coverage of important areas.  This is represented in the following diagram.

 

 

The Cameras.  The cameras have been positioned in terms of distance above the ground, direction and range so that the entire yard is covered, with the most important things having coverage from at least two angles.

Three of the actual cameras that are used are made by IQinvision.  The other is made by Panasonic.

  • cam-01 - IQinvision IQeye3
  • cam-02 - Panasonic HCM280
  • cam-03 - IQinvision IQeye301
  • cam-04 - IQinvision IQeye601
     

Several of the main competitors in this market are IQinvision, Sony, Panasonic, Toshiba, Axis Communications and Visual Data.

In order to use these over a computer network the video streams from the cameras are broken up into JPEGs.  These JPEGs are typically between 35KB and 200KB.  Though for HDTV they can be more on the size of 900KB with resolutions of 1280 x 720 pixels.

To give you a sense of the bytes of information that need to be transmitted over the network you also need to know how many frames or JPEGs need to be transmitted per second.  Some possibilities are listed in the following table.

 

 
frame size frames/sec  Mbps/camera
35KB 7 1.9140 Mbps/camera
200KB 7 10.9375 Mbps/camera
900KB 2 14.0625 Mbps/camera

 

The calculation for the conversion of the 200KB images follows.  You want to make sure to notice the use of the units.

 

 

So you can see that you can get quite a few cameras on a switches Fast Ethernet network without having a lot of problems!  ABCO can use their regular Fast Ethernet LAN to handle the information associated with these surveillance cameras and their internal operations.  Though it is important to remember how much information needs to be transmitted, particularly once you want to monitor things more remotely via the Internet.

It turns out that each of these network cameras has several built in capabilities.  These capabilities are likely to be somewhat surprising at first blush, but then one realizes their importance.

  • FTP client
    • an FTP client is embedded in the operating system of the camera and it sends JPEGs to an FTP server
  • HTTP server
    • live video feeds are done via the HTTP server
    • allows up to 10 simultaneous connections
  • video camera

It is also the case that each camera has its own static IP address.  Though, they could likely be configured through DHCP by a DHCP server, this installation doesn't have a DHCP server.

Database Storage.  The video streams are fed via the 100Mbps Ethernet to a database server that allows later playback.  This is done with a Terabyte Digital Video DB.  Each frame is stored in the database.  These streams/frames are retained for 30 days. 

Something called FrameRender retrieves each individual JPEG and drops it in the BLOB field of the DB record.   

The record structure:

  • IMAGE - BLOB( binary )

  • WHEN -  String representing the date & time stamp of the video frame!

The DB consists of multiple DBF tables. Each table up to 2 GB.  The DB serves as input for the Playback module.

The Network.  The logical network diagram for ABCO Construction is given in the following image.  This diagram focuses on the surveillance portion of the network and the desire to get remote playback via the Internet.  There is a firewall to protect the internal network.  Network authentication is used internally to help protect the systems.

 

 

 

When off premises, something called RemoteControl is used to view surveillance information.  Obviously, there are issues about getting such streams to move well across the open Internet.

For starters, the connection the business has to the Internet is a DSL line.  It doesn't seem to have any unusual upload capacities associated with trying to stream video/frames offsite.

There are also issues of what sort of feed is available at the location where remote playback is desired.  Though, most DSL connections are asymmetrically configured to give better download than upload bandwidth and this will work in favor at this end.

In between, we have the Internet itself, with unknown capacity.  Is it worth it for the business to lease some capacity?