CoTree: Region-free and Decentralized Edge Server Cooperation

Abstract

In MEC, because the traffic distribution in MEC is heterogeneous and dynamic, it is difficult for an individual edge server to provide satisfactory computation service anytime and anywhere. These issues motivated the researchers to study the cooperation among edge servers. The previous works have disadvantages since the cooperated region in these algorithms is limited within one-hop. The performance of MEC can be improved further by releasing the restriction of cooperation region, which is challenging. Therefore, we propose a new decentralized and region-free edge server cooperation approach for task offloading in MEC, named CoTree. In CoTree, the cooperation region is not limited. Each server forms its own basic cooperation unit and calculates its announced capability based on the BCU. The server's capability, the processing delay, the task and calculation result forwarding delay are considered during the calculation. The task division strategy bases on the real capability of host-server and the announced capability of cooperation-servers. This cooperation process is recursive and will be terminated once the terminal condition is satisfied. The simulation results demonstrate the advantages of CoTree over previous works.