GRaNADA: A NetworkAware and EnergyEfficient PaaS Cloud Architecture Current estimated energy usage of data centers and core networks adds up to 3% of the global energy production, while only 42,3% of the population is estimated to be connected. In the last 14 years the number of Internet users has increased tenfold, especially in the period 20102014. According to this growing trend, Internetu0027s energy consumption is meant to be a very critical issue in the near future. The emergence of cloud computing represented a major breakthrough in Internet technologies and in reduction of energy consumption. However, due to its centralized nature, this improvement in energyefficiency has not been reflected in networksu0027 consumption. In this paper, we analyze energy consumption of cloud networks, and present GRaNADA, a semidecentralized PlatformasaService architecture. Through simulations, we show an overall saving much of the energy consumed in standard centralized clouds with our approach.

Multilevel resource allocation for performanceaware energyefficient cloud data centers The massive power consumption of data centers has been a recurring concern in current research. In cloud environments, lots of methods are being adopted that aim for energy efficiency. However, although such methods enable the decrease in power consumption, they regularly affect application performance. In this paper, we present a multilevel resource allocation approach towards dynamic network bandwidth at the physical substrate, managing different powersaving states and workload allocation at the cloud infrastructure at the same time employ virtual machine allocation and selection policies at the cloud platform. In order to evaluate our approach, tests were carried out in a simulated environment using scaleout application on a dynamic cloud infrastructure. Results showed that our proposal presents a better balance regarding a more energyefficient data center with a smaller impact on application performance when compared with other works discussed in the literature.