studio dross presents::
the art of internet sonar

the internet ping utility enables us to quickly determine whether a particular internet address is reachable - in other words, claimed by a computer on the network. we can automate this process to operate on ranges of internet addresses, allowing us to track the number and identity of claimed addresses in a range. by this process, we can create maps of such address blocks over time, each point indicating whether a particular address was responding at a particular time.

internet service providers typically allocate blocks of addresses for use by their customers. in the past, these blocks were dynamically allocated on demand to dial-up customers. more recently, many internet users are permanently connected via broadband technologies, raising the need for static addresses which are assigned to a particular customer all of the time. this circumstance makes it possible to not only track the number of claimed addresses, but to track the times a particular customer's computer is turned on, and therefore responding to pings.

by periodically scanning address blocks known to belong to such internet provider address pools, we can gain insight into aspects of local computer use, which are indicative of other local sociological factors. for instance, such graphs reflect the daily cycles of night and day, as pre-dawn hours typically see the fewest number of connected computers. we can also see the effects of work hours: many people turn on their home computers upon returning from work, causing a spike in the graph density around that time. home office workers will have much different connectivity patterns from those who leave home to go to work.

perhaps even more interestingly, network sonar maps have intrinsic qualities which place them in the realm of art. beyond the subjective aesthetic value of the visual representations of such maps (see on the right the vertical map of a block belonging to a british isp), the process of their making is of particular interest. essentially, the lines drawn on such a map are determined by the actions of all the people who control the computers at the addresses in question. if we are making a sonar map of a 256-address block, typically around 256 people, acting over many days, will affect how the map turns out. interestingly, each is helping to create this work of art, somewhere on the other side of the world, completely unknowingly, simply by pressing the on/off button on their computer at particular times, in the normal course of their daily lives.

the complete maps can be mined for more specific information. they constitute a peculiar kind of data visualization: one which includes exactly the information being visualized: not a bit more nor less. we can examine particular lines for information on specific addresses, or collapse address blocks or time periods to produce summarized composite data. these lines of inquiry would call for different visual representations, opening more opportunities for producing interesting graphics.