The expansion of Internet has led to a variety of directly accessible devices and services. Nowadays, companies tend to increase the number of Internetfacing services in order to ensure higher visibility, and accessibility towards end-users. Nonetheless, this profound expansion towards an “Internet of Things” brings new opportunities to malicious actors. As a result, novel cyber-physical attacks bring new challenges to systems administrators in order to accommodate traditional user requests with security prerequisites. Therefore, in this paper we propose a novel approach for historical Internet connectivity assessment of services. The technique uses the output of the popular Shodan search engine to infer the lifetime of different Internet-facing services. Experimental results conducted on IP address blocks attributed to six different institutions distributed across four sectors (university, telecommunications, banking, and power) show different possible service lifetime patterns.
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