As the Internet becomes the public square and the marketplace of our world, it is increasingly becoming a contested terrain. Its potential for diffusing knowledge and subverting the traditional channels of information is tremendous. So it is not surprising that governments, corporations and even seemingly innocuous social networking sites all want to control and influence the way the Internet operates. It's easy to see why. Close to a third of humanity is linked to this system and the dramatic growth in Internet usage over the past decade is set to explode in coming years. So is its commercial promise. Latha Jishnu looks at events in the US following the WikiLeaks exposé of its diplomatic cables, and in the hot spots of political turmoil across the world to understand the significance of the Internet in today's interconnected world and the threats it faces. Arnab Pratim Dutta explains the technology used to block access to the Net