Nguyen Huu Thanh

mSCTP-based proxy in support of multimedia session continutity and QoS for IMS-based networks

This paper presents a new approach that supports session continuity for multimedia services in IMS-based heterogeneous environment. We propose a new component in the IMS domain, namely an proxy based on mSCTP (mobile stream control transmission protocol) that acts as an anchor point for soft vertical handover of mobile nodes, which have multiple physical interfaces (e.g., WLAN/UMTS). The mSCTP-based proxy also supports QoS provisioning and adaptation for the mobile nodes when moving in a heterogeneous wireless environment. Results show that the signaling cost for handover in our approach can be up to 23 times smaller than that in the conventional approach.

ECODANE: A customizable hybrid testbed for green data center networks

In this paper we propose a new testbed architecture that combines hardware network devices with virtual emulation test environment to improve scalability, flexibility and accuracy. The testbed enables to design and experiment new concepts for energy-efficient data center. It is based on OpenFlow, a Software Defined Networking (SDN) technology that facilitates the deployment of energy-aware protocols and mechanisms.

Enabling experiments for energy-efficient data center networks on OpenFlow-based platform

Energy efficiency is becoming increasingly important in todays networking infrastructure, especially in data center networks. Recent surveys have shown that the energy utilized by computing and networking components in a data center considerably contributes to its operation costs. Therefore performance and energy issues are important for the design of large multi-tier data centers that can support multiple services. However, the design, analysis, and experiments of such a large and complex system often suffer from the lack of appropriate experimental environments. With this motivation, we present a platform for in-depth analysis of energy-aware data center networks. The platform is a combination of hardware testbed and emulation. Based on real traffic patterns measured in a data center and with the energy model obtained from realistic measurements on NetFPGA-based OpenFlow switches, the experimental platform is designed to capture details of energy consumed by all network components such as links, ports, and switches under different scenarios.

Performance evaluation of multiple RPL routing tree instances for Internet of Things applications

To meet the development of Internet of Things (IoT), IETF has proposed IPv6 standards working under low-power and low-cost constraints. In this paper, we provide insights on RPL (routing protocol for low power and lossy networks) under the condition of multiple RPL instances. For the study, we use the Contiki operating system, together with the COOJA simulator. Our work investigates the use of two distinctive objective functions under multiple RPL instances for differentiating QoS at network layer in WSNs. The metrics evaluated include routing tree convergence, latency and packet delivery ratio. The study can also serves as a basis for future enhancement of the use of multiple RPL instances for a plethora of IoT applications.

A multi-criteria-based DDoS-attack prevention solution using software defined networking

Software-Defined Networking (SDN) has become a promising network architecture in which network devices are controlled by a SDN Controller. Employing SDN offers an attractive solution for network security. However the attack prediction and Prevention, especially for Distributed Denial of Service (DDoS) attacks is a challenge in SDN environments. This paper, analyzes the characteristics of traffic flows up-streaming to a Vietnamese ISP server, during both states of normal and DDoS attack traffic. Based on the traffic analysis, an SDN-based Attack Prevention Architecture is proposed that is able to capture and analyze incoming flows on-the-fly. A multi-criteria based Prevention mechanism is then designed using both hard-decision thresholds and Fuzzy Inference System to detect DDoS attack. In response to determining the presence of attacks, the designed system is capable of dropping attacks flows, demanding from the control plane.

Power aware OpenFlow switch extension for energy saving in data centers

Data centers play an important role in our daily activities. The increasing demand for data centers in both scale and size has led to huge energy consumption. The cost and environmental impact of data centers increases due to large amounts of carbon emissions. One solution to this problem is to intelligently control the power consumption of switches used in data centers. This paper proposes an extension to OpenFlow switches to support different power saving modes. The extension includes defining new messages in Openflow standard and designing an OpenFlow Switch Controller (OSC) that is able to turn on/off switches and disable/enable ports. To prove the soundness of the proposed extension, the OSC has been used to control the NetFPGA based OpenFlow switches in the ECODANE framework. The results presented in this paper can aslo be used by the OpenFlow compliant switches manufacturer or by power aware research community.

Multimedia session continuity with context-aware capability in IMS-based network

In this paper we firstly proved that Mobile IP protocols are designed for mobility but not for session continuity. In contradiction, mSCTP (mobile Stream Control Transmission Protocol) appears to be the best protocol with regard to session continuity support, however it does not support location management mechanisms, thus context-aware QoS as well as other mechanisms based on knowledge of location are hardly accommodated. On the other hand, the standardized IP Multimedia Subsystem (IMS) solution initially introduced by 3GPP adopts the policy-based QoS model to map users subscription to a pre-defined QoS level, to apply service-based charging and to prevent Theft-of-Service. In this article we propose a new approach that integrates mSCTP into IMS networks to facilitate session continuity and to provide mechanisms for service control. It is realized by a proxy based on mSCTP (mobile Stream Control Transmission Protocol) that acts as an anchor point for soft vertical handover of mobile nodes, which have multiple physical interfaces (e.g., WLAN/UMTS). The mSCTP-based proxy also supports QoS provisioning and adaptation for the mobile nodes when moving in a heterogeneous wireless environment. Results show that the signaling cost for handover in our approach can be up to 23 times smaller than that in the conventional approach.

QoE-aware resource provisioning and adaptation in IMS-based IPTV using OpenFlow

This article presents the architecture design and experimental evaluation of a QoE-aware flexible-QoS-control next-generation IPTV network. The architecture extends the IMS service control functionality by providing an efficient application-specific service control approach based on user satisfaction on the connectivity. The validation NGN testbed uses OpenFlow network virtualization between individual components.

OpenFlowSIA: An optimized protection scheme for software-defined networks from flooding attacks

In this paper, we propose an optimized protection mechanism (OpenFlowSIA) for Software-Defined Networks from flooding attacks (Distributed Denial-of-Service) based on Support Vector Machine and our proposed algorithm called the Idle-timeout Adjustment (IA). Our methodology not only utilizes SVM advantages in classification such as high accuracy and little processing time, but also applies effectively the IA algorithm and coherent policies to protect network from resource exhaustion caused by flooding attacks, particularly for the SDN controller and OpenFlow switches. Through comprehensive experiments, the OpenFlowSIA scheme illustrates that it can be an innovative solution to secure and save the network resources under flooding attacks in the Software-Defined Networks.

A reliable analyzer for energy-saving approaches in Large Data Center Networks

Nowadays a big effort has been paid to make energy-efficient Data Center Networks (DCNs). There are several proposed solutions to reduce the energy consumption in DCN. However, for researchers, it is difficult to evaluate the energy saving performance of those approaches in a large-size network due to the testbed/emulation environment limitation. In this paper we construct a Performance Evaluation Simulator (called GreenDC Analyzer) that can model a large DCN of thousands of servers. The tool is shown to have a reliability and flexibility in processing and providing accurate and stable performance evaluations with various switch types, and different energy-saving schemes under the same traffic conditions. The tool also allows us to have a deeper investigation of the energy saving performance for the two well-known energy-saving schemes: Power Scaling and Idle Logic. In the bottom line, the Analyzer could be a useful tool for researchers to study pros and cons of different energy-saving approaches in a data center.