The International Subversives

later. When they began looking around, they could not believe what they had found. The system had one of the weirdest struc- tures they had ever come across.

Most large networks have a hierarchical structure. Further, most hold the addresses of a handful of other systems in the network, usually the systems which are closest in the flow of the external network.

But the NorTel network was not structured that way. What the IS hackers found was a network with no hierarchy. It was a totally flat name space. And the network was weird in other ways too. Every computer system on it contained the address of every other computer, and there were more than 11 000 com- puters in NorTel's worldwide network. What the hackers were staring at was like a giant internal corporate Internet which had been squashed flat as a pancake.

Mendax had seen many flat structures before, but never on this scale. It was bizarre. In hierarchical structures, it is easier to tell where the most important computer systems - and information - are kept. But this structure, where every system was virtually equal, was going to make it considerably more difficult for the hackers to navigate their way through the network. Who could tell whether a system housed the Christmas party invite list or the secret designs for a new NorTel product?

The NorTel network was firewalled, which meant that there was virtually no access from the outside world. Mendax reckoned that this made it more vulnerable to hackers who managed to get in through dial-ups. It appeared that security on the NorTel network was relatively relaxed since it was virtually impossible to break in through the Internet. By sneaking in the backdoor, the hackers found themselves able to raid all sorts of NorTel sites, from St Kilda Road in Melbourne to the corpora- tion's headquarters in Toronto.

It was fantastic, this huge, trusting network of computer sites at their fingertips, and the young hackers were elated with the anticipation of exploration. One of them described it as being