This paper proposes a rate adjustment scheme for inbound data traffic on a virtualized host. Most prior studies on network virtualization have only focused on outbound traffic, yet many cloud applications rely on inbound traffic performance. The proposed scheme adjusts the inbound rates of virtual network interfaces dynamically in proportion to the bandwidth demands of the virtual machines.

In a Cache Coherent Non-Uniform Memory Access (CC-NUMA) system, memory transactions can be classified into two types: inter-node transactions and intra-node transactions. Because the latency of inter-node transactions is usually hundreds times larger than that of intra-node transactions, it is important to reduce the latency of inter-node transactions. Even though the remote cache in the CC-NUMA systems improves the latency of inter-node transactions through caching the remote memory lines, the remote and processor caches of snoop-based CC-NUMA systems have to retain the multi-level cache inclusion property for the simplification of snooping. The inclusion property degrades the cache performance by following factors. First, all the remote memory lines in a processor cache should be preserved in the remote cache of the same node. Second, a line replacement at the remote cache replaces the same address line in the processor caches, which does not comply with the replacement policy of the processor caches. In this paper, we propose Access-list which renders the inclusion property unnecessary, and evaluate the performance of the proposed system by program-driven simulation. From the simulation results, it is shown that the miss rates of caches are reduced and the efficiency of the snoop filtering is similar to the system with the inclusion property. It turns out that the performance of the proposed system is improved up to 1.28 times.

We achieve concurrent access to WiFi and WiMAX networks on a mobile terminal equipped with a common RF subsystem by providing time-interleaved RF access control schemes to both of the MAC layers. We propose cooperative and competitive sharing schemes, neither of which requires any modification to other network components. We implement our schemes on a WiFi/WiMAX dual-mode SoC platform. Experimental results show that these schemes work and have affordable overheads.

The audio delay is becoming an important factor in audio streaming over short-range wireless network. In this study, we propose an efficient two-level delay control method, called frame sequence adaptation and audio sampling frequency compensation, for achieving stable audio delay with a small variation. To prove the effectiveness of our scheme, we implemented and evaluated the scheme on a Bluetooth network. Experimental results show that our scheme can control audio delay robustly and remove phase shift problem in multi-channel stereophonic audio broadcasting as well.