Using Network Processor to Establish Security Agent for AODV Routing Protocol

Network Processor (NP) is optimized to perform special network functionalities. It has highly parallel processing architecture to achieve high performance. Ad hoc network is an exciting research aspect due to the characters of self-organization、 dynamically changing topology and temporary network life. However, all the characters make the security problem more serious. Denial-of-Service (DoS) attack is the main puzzle in the security of Ad hoc network. A novel NP-based security scheme is proposed to combat the attack in AODV routing protocol. Security agent is established by a hardware thread in NP. Agent can update itself at some interval by the trustworthiness of the neighbor nodes. Agent can trace the RREQ and RREP messages stream to aggregate the key information to link list and analyze them by intrusion detection algorithm. NS2 simulator is expanded to validate the security scheme. Simulation results show that NP-based security scheme is highly effective to detect and block DoS attack

Techniques in Mapping Router-Level Internet Topology from Multiple Vantage Points

Abstract. Accompanying the Internet rapid expansion and the great changes in Internet underlying topology, research communities have paid ever-increasing attention to the challenging task of measuring Internet topology. This paper discusses the limitation of using public traceroute servers for router level topology measurement. In our distributed three-level architecture for mapping individual ISP topologies by a third party, an on-demand probing at each hop and centralized DNS query are employed to reduce network overload and improve probe efficiency. The effects of these two techniques are exhibited in this paper.

Stateful Inspection Firewall Session Table

Stateful Inspection is a key technology to network devices such as routers and firewalls. Existing session table architectures of Stateful Inspection devices store all session information in a single entry, which causes high time cost of session table timeout processing. In this paper we present a new architecture which divides a session entry into two parts, and designs different data structures for each other. The new architecture can improve the performance of session table greatly. A new PATRICIA algorithm is proposed to organize session table, which is proved to be an optimal 2-ary trie for fixed-length match. An ASIC is implemented for the architecture and corresponding algorithms. Both theoretical and experimental results show that the new architecture has bette

An Automated and Interpretable Machine Learning Scheme for Power System Transient Stability Assessment

Many repeated manual feature adjustments and much heuristic parameter tuning are required during the debugging of machine learning (ML)-based transient stability assessment (TSA) of power systems. Furthermore, the results produced by ML-based TSA are often not explainable. This paper handles both the automation and interpretability issues of ML-based TSA. An automated machine learning (AutoML) scheme is proposed which consists of auto-feature selection, CatBoost, Bayesian optimization, and performance evaluation. CatBoost, as a new ensemble ML method, is implemented to achieve fast, scalable, and high performance for online TSA. To enable faster deployment and reduce the heavy dependence on human expertise, auto-feature selection and Bayesian optimization, respectively, are introduced to automatically determine the best input features and optimal hyperparameters. Furthermore, to help operators understand the prediction of stable/unstable TSA, an interpretability analysis based on the Shapley additive explanation (SHAP), is embedded into both offline and online phases of the AutoML framework. Test results on IEEE 39-bus system, IEEE 118-bus system, and a practical large-scale power system, demonstrate that the proposed approach achieves more accurate and certain appropriate trust solutions while saving a substantial amount of time in comparison to other methods

Triboelectric Nanogenerator as a Self-Powered Communication Unit for Processing and Transmitting Information

In this paper, we demonstrate an application of a triboelectric nanogenerator (TENG) as a self-powered communication unit. An elaborately designed TENG is used to translate a series of environmental triggering signals into binary digital signals and drives an electronic–optical device to transmit binary digital data in real-time without an external power supply. The elaborately designed TENG is built in a membrane structure that can effectively drive the electronic–optical device in a bandwidth from 1.30 to 1.65 kHz. Two typical communication modes (amplitude-shift keying and frequency-shift keying) are realized through the resonant response of TENG to different frequencies, and two digital signals, <i>i.e.</i>, “1001” and “0110”, are successfully transmitted and received through this system, respectively. Hence, in this study, a simple but efficient method for directly transmitting ambient vibration to the receiver as a digital signal is established using an elaborately designed TENG and an optical communication technique. This type of the communication system, as well as the implementation method presented, exhibits great potential for applications in the smart city, smart home, password authentication, and so on