An efficient load balancing scheme for resilient search in KAD peer to peer networks

In this paper, we propose an efficient multiple hashes method (called KAD-N) to balance peer loads in the KAD (Kademlia) network. Note that N is the maximum hash times, determining by a cost-effectiveness factor. This method hashes the keyword of an object r times to produce a key for publishing objects, where r is a random number and 1 ≤ r ≤ N. Simulation results show that the distribution of indexes is more balanced using the proposed KAD-N method. We found out that N = 7 (KAD-7) is the optimal setting in our simulation environment. We used a standard deviation to evaluate the proposed load balancing method. Simulation results also show that KAD-7 has the search hit rate close to 100% and the standard deviation is 44% less than that of the KAD (i.e., KAD-1), which means the proposed method is more load balancing than the KAD. However, KAD-7 has 7% extra traffic overhead. By increasing the search hit rate, KAD-N improves the search resilience of KAD networks with failed peers. Furthermore, the proposed KAD-N method can easily be extended to other DHT-based P2P networks.