Random Round Robin Research Articles

A Defense Mechanism Based on Improved Allocation Strategy of VMs Co-Resident Attack in Power Cloud Platform

Background: Cloud platform is widely applied in the field of electric power. Virtual machine co-resident attack is one of the fundamental security threats to the existing power cloud platform. Objective: This paper addresses a mechanism so as to defend virtual machine co-resident attack on power cloud platform. Methods: Our defense mechanism wields the DBSCAN algorithm to classify the results through the random forest and adopted improved virtual machine deployment strategy which combines the advantages of random round robin strategy and maximum/minimum resource strategy so as to deploy virtual machines. Results: We made a simulation experiment on power cloud platform of State Grid and verified the effectiveness of proposed defense deployment strategy. Conclusion: After the virtual machine deployment strategy is improved, the coverage of the virtual machine is remarkably reduced which proves that our defense mechanism achieves some effect of defending the virtual machine from virtual machine co-resident attack.

Efficient Scheduling Algorithms for Bluetooth Scatternets

When more than seven devices are connected in a Bluetooth scatternet, bridge devices are used to connect two piconets to the scatternet. To deal with possible data transmissions between different piconets, the bridge device must frequently switch to different masters. Suppose, however, that a bridge is serving a piconet and the master in another piconet is calling it at the same time, the calling master has to wait until the bridge completes the previous service. Such transmission delay may accumulate over a long period and the performance of the whole Bluetooth network will degrade significantly. In this work, two new scheduling protocols, namely the static schedule and the hybrid schedule were implemented in an effort to smooth this kind of transmission delay in Bluetooth networks. In this static schedule the rendezvous points between piconets are coordinated by distributing them by using a graph edge coloring technique. In case of a heavy traffic load, the static schedule is expected to perform well. On the other hand, in case of a light traffic load, the static schedule may cause long and unavoidable routing delays even when there is no transmission between piconets; in this case a naive random round-robin (RR) schedule in each piconet is more appropriate. Thus, in the hybrid schedule, each master initially runs a RR scheme in its piconet. When the traffic load is heavier than a predefined threshold value, it runs the static schedule. Finally, simulations were conducted by using an ns-2 simulator and Bluehoc to demonstrate the efficiency and effectiveness of the proposed scheduling protocols.