Misbehavior in Nash Bargaining Solution Allocation

Nash Bargaining Solution (NBS) has been broadly suggested as an efficient solution for problem of fair allocation of multiple resources, namely bandwidth allocation in datacenters. In spite of being thoroughly studied, and provably strategyproof for most scenarios, NBS-based allocation methods lack research on strategic behavior of tenants in case of proportionality of resource demands, which is common in datacenter workloads. We found that misbehavior is beneficial: by lying about bandwidth demands tenants can improve their allocations. We show that the sequence of selfish improvements leads to trivial demand vectors for all tenants. It essentially breaks sharing incentives which are very important for datacenter networks. We analytically prove that tenants can misbehave for 2 and 3 tenants cases. We show that misbehavior is possible in one recently proposed NBS-based allocation system if demands proportionality is taken into account. Monte-Carlo simulations were done for 2 − 15 tenants to show a misbehavior possibility and its impact on aggregated bandwidth. We propose to use another game-theoretic approach to allocate bandwidth in case of proportional demands. That method performs significantly better on average than NBS after misbehavior.