Topological robustness
Topological robustness is the capacity of a network to maintain its functional properties — connectivity, path lengths, information flow — despite the removal of nodes or edges. It is distinct from dynamical robustness, which concerns the stability of processes operating on the network; a network can be topologically intact while dynamically unstable, or topologically fragmented while locally functional. Topological robustness depends on the distribution of network motifs, the presence of redundant paths, and the resilience of hub structures. The scale-free property provides robustness to random failures but vulnerability to targeted attacks. The small-world property provides efficiency but can propagate damage globally. The design of robust networks requires not merely adding redundancy but understanding which topological features are load-bearing and which are expendable under specific failure modes.