Access Point Decoding Coded MapReduce for Tree Fog Network

Recently, a Hybrid Coded MapReduce for server-rack architecture has been proposed. In the data shuffling phase, the total communication cost is divided into intra-rack communication cost and cross-rack communication cost. Compared with the general Coded MapReduce, intra-rack communication cost is reduced with increased cross-rack communication cost. In this paper we focus on the three-tier tree topology under the Fog Computing environment, in which fog nodes are connected wirelessly by access points. The communication cost is divided into uplink and downlink cost, and computing and storage can be performed by access points. We introduce Access Point Decoding Hybrid Coding MapReduce scheme where access points instead of fog nodes participate in decoding. Theoretical analyses and simulations show that the total communication cost of secondary access points during the data shuffling phase is reduced further compared with the Hybrid Coded MapReduce in the case of redundancy factor of 2.