A high-performance Two-Phase Multipath scheme for data-center networks

International audienceMultipath forwarding has been recently proposed to improve utilization in data centers leveraged by its redundant network design. However, most multipath proposals require significant modifications to the tenants’ network stack and therefore are only feasible in private clouds. In this paper, we propose the Two-Phase Multipath (TPM) forwarding scheme for public clouds. The proposal improves tenants’ network throughput, whereas keeping unmodified network stack on tenants. Our scheme is composed of a smart offline configuration phase that discover optimal disjoint paths, and a fast online path selection phase that improves flow throughput at run time. A logically centralized manager uses a genetic algorithm to generate and install sets of paths, summarized into trees, during multipath configuration, and a local controller performs the multipath selection based on network usage. We analyze TPM for different workloads and topologies under several scenarios of usage database locations and update policies. The results show that our proposal yields up to 77% throughput gains over previously proposed approaches

Evaluating Virtual Router Performance for a Pluralist Future Internet

Abstract—Internet Service Providers resist innovating in the network core, fearing that deploying a new protocol or service compromises the network operation and their profit, as a consequence. Therefore, a new Internet model, called Future Internet, which enables core innovation, must accommodate new protocols and services with the current scenario, isolating each protocol stack from others. Virtualization is the key technique that provides concurrent protocol stack capability to the Future Internet elements. In this paper, we evaluate the performance of three widespread virtualization tools, Xen, VMware, and OpenVZ, considering their use for router virtualization. We conduct experiments with benchmarking tools to measure the overhead introduced by virtualization in terms of memory, processor, network, and disk performance of virtual routers running on commodity hardware. We also evaluate the effects of the increasing number of virtual machines on Xen network virtualization mechanism. Our results show that Xen best fits virtual router requirements. Moreover, Xen fairly shares the network access among virtual routers, but needs further enhancement when multiple virtual machines simultaneously forward traffic. Keywords-Xen; OpenVZ; VMware; Hypervisor; Virtual Router I

FITS: A flexible virtual network testbed architecture

International audienceIn this paper, we present the design and implementation of FITS (Future Internet Testbed with Security), an open, shared, and general-purpose testbed for the Future Internet. FITS defines an innovative architecture that allows users running experiments with new mechanisms and protocols using both Xen and OpenFlow on the same network infrastructure. FITS integrates several recognized state-of-the-art features such as plane separation, zero-loss network migration, and smartcard-driven security access, to cite a few. The current physical testbed is composed of nodes placed at several Brazilian and European institutions interconnected by encrypted tunnels. Besides presenting the FITS architecture and its features, we also discuss deployment challenges and how we have overcome them