SUMMARY
The goal of data center network is to interconnect a massive number of servers so as to provide reliable and scalable computing and storage infrastructure for cloud-based Internet services and data-intensive scientific applications. Recent studies reveal that the network elements consume 10~20% of the overall power in a data center, which has introduced a challenge to reducing network energy cost without adversely affecting network performance. Considering unique features of traffic patterns and network topologies in data centers, this paper proposes a novel Network Element Scheduling Scheme (NESS) to reduce data center energy consumption from the networking perspective. The core idea is to turn on only a minimal subset of network elements to satisfy routing requirements, and put to sleep or shut down the rest unneeded ones for energy saving. In NESS, the logical network architecture formed by the active elements not only achieves the basic purpose for server interconnections in data centers, but also can support multi-path routing between pairs of hot servers for load balancing. Simulation experiments are performed in representative data center network topologies, and the results demonstrate the effectiveness of NESS in energy conserving on network elements in data centers.