Border Patrol getting first part of 'virtual fence'
Although the government has plans to extend the network of cameras, ground sensors and radar along most of the border, officials said they will draw on lessons from the first two segments in southern Arizona as they contemplate whether and where to build more sections and how fast to complete them. http://www.washingtontimes.com/news/2009/dec/01/border-patrol-getting-first-part-of-virtual-fence/