Quality of Service in Software Defined Networking

Software Defined Networking SDN promises to provide a powerful way to introduce Quality of Service QoS concepts in today s communication networks SDN programmatically modifies the functionality and behavior of network devices using single high level program Software Defined Networking SDN instantiation OpenFlow has been designed according to these properties The realization of Quality of Service QoS concepts becomes possible in a flexible and dynamic manner with SDN This paper focuses on the existing architectures parameter such as response time switch capacity and bandwidth isolation that is calculated here Although concepts of QoS are well researched they were not realized in communication networks due to high implementation complexity and realization costs OpenFlow as the best-known SDN standard so far defines a standard protocol for network control These observations of switch variety may provide SDN application developer s insights when realizing QoS concepts in an SDN-based networ

Transparent Bandwidth Aggregation for Residential Access Networks

We propose, implement, and evaluate a bandwidth aggregation service for residential users that allows to improve the upload throughput of the asymmetric digital subscriber line connection by leveraging the unused bandwidth of neighboring users. The residential access gateway adopts the 802.11 radio interface to simultaneously serve the local home users and to share the broadband connectivity with neighboring access gateways. Differently from previous works, our aggregation scheme is transparent both for local users, who are not required to modify their applications or device drivers, and for neighboring users, who do not experience any meaningful performance degradation. To evaluate the achievable performance and tune the parameters driving the traffic balancing, we developed a fluid model that was shown experimentally to be very accurate. Our proposed scheme is amenable to efficient implementation on Linux networking stack. Indeed, we implemented it and tested in some realistic scenarios, showing an efficient exploitation of the whole available bandwidth, also for legacy cloud storage applications

Defeating network jitter for virtual machines

Virtualization based cloud computing hosts networked applications in virtual machines (VMs), and provides each VM the desired degree of performance isolation using resource isolation mechanisms. Existing isolation solutions address heavily on resource proportionality such as CPU, memory and I/O bandwidth, but seldom focus on resource provisioning rate. Even the VM is allocated with adequate resources, if they can not be provided in a timely manner, problems such as network jitter will be very serious and significantly affect the performance of cloud applications like internet audio/video streaming. This paper systematically analyzes and illustrates the causes of unpredictable network latency in virtualized execution environments. We decouple the design goals of resource proportionality from resource provisioning rate, and adopt divide-and-conquer strategy to defeat network jitter for VMs: (1) in VMM CPU scheduling, we differentiate self-initiated I/O from event-triggered I/O, and individually map them to periodic and aperiodic real-time domains to schedule them together; (2) in network traffic shaping of VMs, we introduce the concept of smooth window to smooth network latency and apply closed-loop feedback control to maintain network resource consumption. We implement our solutions in Xen 4.1.0 and Linux 2.6.32.13. The experimental results with both real-life applications and low-level benchmarks show that our solutions can significantly reduce network jitter, and meanwhile effectively maintain resource proportionality.published_or_final_versionThe 4th IEEE International Conference on Utility and Cloud Computing (UCC 2011), Victoria, NSW, 5-8 December 2011. In Proceedings of the 4th IEEE-UCC, 2011, p. 65-7

Cooperative data transfers for 5G networks

The demand for higher capacity, higher data rate and larger bandwidth has driven the research and industrial world to develop next generation wireless communication technology, namely, the 5G. Among all the approaches proposed for such a high demand, only the cooperative communication approach promises to significantly improve of the performances (capacity, data rate, bandwidth, etc.) with a low cost. In this thesis, we propose a D2D communication scheme as a solution for the out-door scenario and a cooperative scheme among the access infrastructures as the in-door scenario solution. In the first part, we address the implementation of content-centric routing in a D2D architecture for Android devices based on WiFi Direct, a protocol recently standardised by the Wi-Fi Alliance. After discussing the creation of multiple D2D groups, we introduce novel paradigms featuring intra- and inter-group bidirectional communication. We then present the primitives involved in content advertising and requesting among members of the multi-group network. In addition to the communications, we also devise a mechanism to enable the devices to spontaneously establish the multi-group D2D network. Finally, we evaluate the performance of our architecture and the network formation mechanism in a real testbed consisting of Android devices. In the second part, we propose, implement and evaluate a bandwidth aggregation service for residential users that allows to improve the upload throughput of the ADSL connection by leveraging the unused bandwidth of neighboring users. The residential access gateway adopts the 802.11 radio interface to simultaneously serve the local home users and to share the broadband connectivity with neighboring access gateways. Differently from previous works, our aggregation scheme is transparent both for local users, who are not required to modify their applications or device drivers, and for neighboring users, who do not experience any meaningful performance degradation. In order to evaluate the achievable performance and tune the parameters driving the traffic balancing, we developed a fluid model which was shown experimentally to be very accurate. Our proposed scheme is amenable to efficient implementation on Linux networking stack. Indeed, we implemented it and tested in some realistic scenarios, showing an efficient exploitation of the whole available bandwidth, also for legacy cloud storage applications

SDN-BASED MECHANISMS FOR PROVISIONING QUALITY OF SERVICE TO SELECTED NETWORK FLOWS

Despite the huge success and adoption of computer networks in the recent decades, traditional network architecture falls short of some requirements by many applications. One particular shortcoming is the lack of convenient methods for providing quality of service (QoS) guarantee to various network applications. In this dissertation, we explore new Software-Defined Networking (SDN) mechanisms to provision QoS to targeted network flows. Our study contributes to providing QoS support to applications in three aspects. First, we explore using alternative routing paths for selected flows that have QoS requirements. Instead of using the default shortest path used by the current network routing protocols, we investigate using the SDN controller to install forwarding rules in switches that can achieve higher bandwidth. Second, we develop new mechanisms for guaranteeing the latency requirement by those applications depending on timely delivery of sensor data and control signals. The new mechanism pre-allocates higher priority queues in routers/switches and reserves these queues for control/sensor traffic. Third, we explore how to make the applications take advantage of the opportunity provided by SDN. In particular, we study new transmission mechanisms for big data transfer in the cloud computing environment. Instead of using a single TCP path to transfer data, we investigate how to let the application set up multiple TCP paths for the same application to achieve higher throughput. We evaluate these new mechanisms with experiments and compare them with existing approaches

BaseFs - Basically Acailable, Soft State, Eventually Consistent Filesystem for Cluster Management

A peer-to-peer distributed filesystem for community cloud management. https://github.com/glic3rinu/basef