The study analyzes the topology of e-mail networks using data from server logs, revealing a scale-free structure and small-world properties. The network consists of 59,912 nodes with a mean degree of 2.88, showing a power-law degree distribution $ n(k) \propto k^{-1.81} $. This indicates that a few nodes (hubs) have a high number of connections, while most have few. The network also exhibits small-world properties, characterized by high clustering and short average path lengths. The e-mail network is undirected, with nodes representing email addresses and links representing emails exchanged. The degree distribution of internal nodes (students) follows a power law $ n_{\mathrm{int}}(k) \propto k^{-1.32} $, while external nodes have underestimated degrees. The network is robust against random node failures but vulnerable to attacks on highly connected nodes. The scale-free nature of the network facilitates the spread of e-mail viruses, as the threshold for infection is lower. This implies that targeted immunization of highly connected nodes is more effective in preventing outbreaks. The study also highlights the potential for using the network's structure for community detection and targeted marketing. The findings suggest that e-mail networks have non-trivial topological features that can be exploited or mitigated. Understanding these features can improve email security by monitoring high-traffic nodes and enhancing network resilience against malicious activities. The study underscores the importance of considering network topology in the design of secure and efficient communication systems.The study analyzes the topology of e-mail networks using data from server logs, revealing a scale-free structure and small-world properties. The network consists of 59,912 nodes with a mean degree of 2.88, showing a power-law degree distribution $ n(k) \propto k^{-1.81} $. This indicates that a few nodes (hubs) have a high number of connections, while most have few. The network also exhibits small-world properties, characterized by high clustering and short average path lengths. The e-mail network is undirected, with nodes representing email addresses and links representing emails exchanged. The degree distribution of internal nodes (students) follows a power law $ n_{\mathrm{int}}(k) \propto k^{-1.32} $, while external nodes have underestimated degrees. The network is robust against random node failures but vulnerable to attacks on highly connected nodes. The scale-free nature of the network facilitates the spread of e-mail viruses, as the threshold for infection is lower. This implies that targeted immunization of highly connected nodes is more effective in preventing outbreaks. The study also highlights the potential for using the network's structure for community detection and targeted marketing. The findings suggest that e-mail networks have non-trivial topological features that can be exploited or mitigated. Understanding these features can improve email security by monitoring high-traffic nodes and enhancing network resilience against malicious activities. The study underscores the importance of considering network topology in the design of secure and efficient communication systems.