The Internal Network Structure that Affects Firewall Vulnerability

Sharing extensive healthcare information is essential for the advancement of medicine and the formulation of effective public health policies. However, it often contains sensitive or personal information, or trade secrets. Certain safety measures are needed to strike a balance between the sharing of data and the protection of such information. A firewall is one of the major safety measures designed to prevent the delivery of protected information by severing harmful connections or limiting the formation of new connections between relevant parties in an information exchange network. Although very simple models suggest firewall vulnerabilities, such models often oversimplify real-world scenarios, neglecting factors like internal connections among nodes and the influence of other information held by nodes. Therefore, we propose several improved models and use them to explore some of the reasons why firewalls fail. Our study finds that firewalls are less effective as the number of network nodes increases, and that both high- and low-degree nodes pose non-negligible risks. The study also raises awareness about the role of internal monitors in preventing leaks. The effectiveness of information leakage control could be increased with the monitor's proximity to the information source. This necessitates a greater focus on internal monitoring, perhaps using information and communication technology.