Degeneracy is the ability of structurally different elements to perform the same function or yield the same output under certain constraints. In contrast to redundancy, which implies identical backups, degeneracy allows diverse components to step in and perform the same or similar role. Mathematically, it is about mapping multiple distinct elements into the same function. In a degenerate system, failure in one part can be compensated by others not structurally linked. System functions are distributed within the system itself or the entire network. This renders faster and more adaptive recovery. In this work, we define and formulate several novel metrics for resource fungibility to address robustness in networks (static/mobile/dynamic).