Eclipse Attack Defense: P2P Sybil Resistance

A peer-to-peer overlay has no central authority to vouch for identities, which is exactly what makes it vulnerable to Sybil attacks: an adversary mints many cheap fake nodes and tries to occupy every slot in a victim's peer table, isolating it inside an attacker-controlled view of the network — an eclipse attack. This simulator renders a victim node and a 3D pool of candidate peers, some honest (green) and some Sybil-controlled (red), and repeatedly runs the victim's peer-selection process. Two independent, real-world defenses — reputation-based trust scoring and subnet/ASN diversity capping — can be toggled on to see how each lowers the effective Sybil fraction the selection process actually encounters, with the eclipse probability P = f_eff^k, live peer-table composition, and a running eclipsed/rounds tally updating after every reselection.