School of Computer and Information Science, Security Research Centre, Edith Cowan University, Perth, Western Australia
Hidden networks arise in high-dimensional network structures when the hidden network members camouflage their existence by appearing randomly connected to the larger network structure, but in reality ensure they remain in persistent contact with one another over time. This paper takes a first step towards determining how to locate such hidden networks through the novel use of group-based social network metrics to characterise the features of hidden networks. Micro, meso and macro-level network analyses of the September 11 network and a selection of popular simulated terrorist network structures will show that the simulated networks are highly visible whereas the hidden networks display low visibility except at the macro level. Moreover these hidden networks aid to camouflage a highly prominent terrorist network of trusted prior contacts.