Billy Hoffman, manager for HP Security Labs at HP Software, and Matt Wood, senior security researcher in HP's Web Security Research Group, will present the findings at the Black Hat conference in Las Vegas next month. They will demonstrate how the system can be used to build a 'darknet', which is a private virtual network running over the public internet.

The researchers say that web browsers are becoming so highly functional that it is now possible to build a darknet using nothing but JavaScript to encrypt communications between the browser and a web server. This contrasts with other darknet systems, such as the Tor technology created by Roger Dingledine at MIT. Tor needs software to be installed on a client computer, and must be taken through a complex set of configurations before it can be used.

Hoffman and Wood's system requires a simple PHP script to be installed on a web server. This script is used to communicate with the JavaScript used in the client browser. It could be used for applications such as anonymous forums and suggestion boxes.

There are some limitations inherent in the system, including restricted bandwidth. Because a client communicates with a single server, it is restricted by the amount of bandwidth available to let server. However, PHP scripts could be installed on multiple servers, which would help alleviate some of the load.

Darknets are becoming an increasingly popular way of making communications private as people become more concerned about online behaviour and identity tracking. Even piracy-focus groups such as The Pirate Bay are becoming interested in building darknets that would enable people to share files with each other without having their IP addresses tracked online.