A four-hour drive from the nearest cellular coverage in the remote highlands of Papua, Indonesia, a new kind of guerilla telecom network is operating, albeit outside the law, using a cheap base station roped into a treetop.

The technology could provide a new model for self-managed “last mile” mobile coverage in the world’s hardest-to-reach areas, where traditional top-down telecommunications business models don’t work.

The project was set up by a team from the University of California, Berkeley.