Speaker: Junning Liu

Title: Load Balancing in Hypercubic Distributed Hash Tables with Heterogeneous Nodes

Recent research has seen considerable work on load balancing for distributed hash tables (DHTs), a fundamental tool in Peer-to-Peer networks. Previous work in this area makes the assumption of homogeneous nodes, where each node has the same power (CPU, memory, network bandwidth, etc.). Here, we study load balancing strategies for hypercubic DHTs in an environment where processors have different capabilities. In particular, we assume that each processor has a size, which represents its resource capabilities. We give a fairness criteria based on minimizing the difference between the processors of the ratio of the fraction of the DHT address space stored on a processor to the size of the processor. For the offline problem, we give a polynomial time algorithm that finds the optimal partitioning of the address space between the processors. We also study the online problem. With an adversary, we give a lower bound on the competitive ratio for online algorithms for this problem. We also describe an algorithm with performance very close to the competitive ratio of the lower bound.

Joint work with Micah Adler