  Ensuring the security of networked systems is a significant problem,
considering the susceptibility of modern infrastructures and technologies to
adversarial interference. A central component of this problem is how defensive
resources should be allocated to mitigate the severity of potential attacks on
the system. In this paper, we consider this in the context of a General Lotto
game, where a defender and attacker deploys resources on the nodes of a
network, and the objective is to secure as many links as possible. The defender
secures a link only if it out-competes the attacker on both of its associated
nodes. For bipartite networks, we completely characterize equilibrium payoffs
and strategies for both the defender and attacker. Surprisingly, the resulting
payoffs are the same for any bipartite graph. On arbitrary network structures,
we provide lower and upper bounds on the defender's max-min value. Notably, the
equilibrium payoff from bipartite networks serves as the lower bound. These
results suggest that more connected networks are easier to defend against
attacks. We confirm these findings with simulations that compute deterministic
allocation strategies on large random networks. This also highlights the
importance of randomization in the equilibrium strategies.
