Packet Filtering and Sampling for Efficient Slow Denial of Service Detection in Resource Scarce IoT Networks

There has recently been considerable interest in automatic detection strategies for recognising application layer security threats such as Hypertext Transfer Protocol (HTTP) Slow Denial of-Service (Slow DoS) attacks in Internet of Things (IoT) networks. Most existing approaches however, fail to take cognisance of the substantial resource constraints imposed upon IoT environments, which limits the applicability and deployment of many Slow DoS detection mechanisms. This paper addresses this significant security threat for resource scarce IoT nodes and networks in proposing an accurate and computationally efficient approach to packet-based intrusion detection of HTTP Slow DoS activity. The paper both critically analyses and measures the impact of applying network attribute filtering and packet sampling to reduce the computational overheads on the resource constrained IoT Slow DoS detection node. The unique solution proposed uses a dataset synthesised from a live IoT environment comprising both legitimate and malicious network events in the form of legitimate HTTP traffic and Slow DoS attacks. Experimental results corroborate that combining filtering at the Border Router of only in-bound packets containing no TCP payload with a systematic packet sampling scheme at a sampling ratio of up to 1:64, the processing overheads on the detection node are significantly reduced. The novel contribution presented is a resource efficient solution, garnered by employing systematic sampling to seamlessly and accurately support selective attribute based intrusion detection of HTTP Slow DoS attacks in IoT networks

A Reliable Real-Time Slow DoS Detection Framework for Resource-Constrained IoT Networks

Slow DoS attacks have proven to pose a significant security threat to low-resource IoT devices and networks, because they can be launched by nodes which consume nominal bandwidth and have limited resource capability. This makes such malicious attacks easy to initiate, but difficult to mitigate. There also exists the recurrent likelihood of misclassifying legitimate nodes, which are incurring slow or poor network connectivity, as malicious activity. Existing intrusion detection systems (IDS) for detecting Slow DoS attacks often require the creation of large datasets for post event analysis. A functional disadvantage of this dataset-driven approach is the sheer volume of data required, due to the high number of network attributes and events collated, which precludes an in-line, real-time IDS detection solution for live IoT networks. This paper presents an innovative IDS detection framework for resource constrained IoT networks. Using a set of only four attributes, a two-step analysis of live IoT network events enables Slow DoS attacks, in the form of Slowloris, to be both efficiently and reliably detected in real-time. In addition, this lightweight IDS framework can accurately distinguish between malicious and genuine nodes encountering slow or intermittent network connections

A Novel Role for ATM in Regulating Proteasome-Mediated Protein Degradation through Suppression of the ISG15 Conjugation Pathway

Ataxia Telangiectasia (A-T) is an inherited immunodeficiency disorder wherein mutation of the ATM kinase is responsible for the A-T pathogenesis. Although the precise role of ATM in A-T pathogenesis is still unclear, its function in responding to DNA damage has been well established. Here we demonstrate that in addition to its role in DNA repair, ATM also regulates proteasome-mediated protein turnover through suppression of the ISG15 pathway. This conclusion is based on three major pieces of evidence: First, we demonstrate that proteasome-mediated protein degradation is impaired in A-T cells. Second, we show that the reduced protein turnover is causally linked to the elevated expression of the ubiquitin-like protein ISG15 in A-T cells. Third, we show that expression of the ISG15 is elevated in A-T cells derived from various A-T patients, as well as in brain tissues derived from the ATM knockout mice and A-T patients, suggesting that ATM negatively regulates the ISG15 pathway. Our current findings suggest for the first time that proteasome-mediated protein degradation is impaired in A-T cells due to elevated expression of the ISG15 conjugation pathway, which could contribute to progressive neurodegeneration in A-T patients

Exploratory trial of a school-based alcohol prevention intervention with a family component: Implications for implementation

Purpose – Involvement of parents/carers may increase effectiveness of primary school-based alcohol-misuse prevention projects through strengthening family-based protective factors, but rates of parental engagement are typically low. This paper reports findings from an exploratory trial of a school-based prevention intervention – Kids, Adults Together (KAT), based on the Social Development Model, which aimed to promote pro-social family communication in order to prevent alcohol misuse, and incorporated strategies to engage parents/carers. The purpose of this paper is to assess the feasibility and value of conducting an effectiveness trial of KAT. Design/methodology/approach – The study was a parallel-group cluster randomised exploratory trial with an embedded process evaluation. The study took place in south Wales, UK, and involved nine primary schools, 367 pupils in Years 5/6 (aged 9-11 years) and their parents/carers and teachers. Questionnaires were completed by pupils at baseline and four month follow-up, and by parents at six month follow-up. Findings – Overall KAT was delivered with good fidelity, but two of five intervention schools withdrew from the study without completing implementation. In total, 50 per cent of eligible parents participated in the intervention, and KAT had good acceptability among pupils, parents and teachers. However, a number of “progression to effectiveness trial” criteria were not met. Intermediate outcomes on family communication (hypothesised to prevent alcohol misuse) showed insufficient evidence of an intervention effect. Difficulties were encountered in identifying age appropriate outcome measures for primary school-age children, particularly in relation to family communication processes. The study was unable to find comprehensive methodological guidance on exploratory trials. Research limitations/implications – It would not be appropriate to conduct an effectiveness trial as key progression criteria relating to intervention and trial feasibility were not met. There is a need for new measures of family communication which are suitable for primary school-age children, and more guidance on the design and conduct of exploratory/feasibility trials. Originality/value – KAT achieved high rates of parental involvement, and its theoretical framework and processes could be adapted by other interventions which experience difficulties with recruitment of parents/carers

Search algorithms as a framework for the optimization of drug combinations

Combination therapies are often needed for effective clinical outcomes in the management of complex diseases, but presently they are generally based on empirical clinical experience. Here we suggest a novel application of search algorithms, originally developed for digital communication, modified to optimize combinations of therapeutic interventions. In biological experiments measuring the restoration of the decline with age in heart function and exercise capacity in Drosophila melanogaster, we found that search algorithms correctly identified optimal combinations of four drugs with only one third of the tests performed in a fully factorial search. In experiments identifying combinations of three doses of up to six drugs for selective killing of human cancer cells, search algorithms resulted in a highly significant enrichment of selective combinations compared with random searches. In simulations using a network model of cell death, we found that the search algorithms identified the optimal combinations of 6-9 interventions in 80-90% of tests, compared with 15-30% for an equivalent random search. These findings suggest that modified search algorithms from information theory have the potential to enhance the discovery of novel therapeutic drug combinations. This report also helps to frame a biomedical problem that will benefit from an interdisciplinary effort and suggests a general strategy for its solution.Comment: 36 pages, 10 figures, revised versio

Thermodynamic analysis of regulation in metabolic networks using constraint-based modeling

<p>Abstract</p> <p>Background</p> <p><it>Geobacter sulfurreducens </it>is a member of the <it>Geobacter </it>species, which are capable of oxidation of organic waste coupled to the reduction of heavy metals and electrode with applications in bioremediation and bioenergy generation. While the metabolism of this organism has been studied through the development of a stoichiometry based genome-scale metabolic model, the associated regulatory network has not yet been well studied. In this manuscript, we report on the implementation of a thermodynamics based metabolic flux model for <it>Geobacter sulfurreducens</it>. We use this updated model to identify reactions that are subject to regulatory control in the metabolic network of <it>G. sulfurreducens </it>using thermodynamic variability analysis.</p> <p>Findings</p> <p>As a first step, we have validated the regulatory sites and bottleneck reactions predicted by the thermodynamic flux analysis in <it>E. coli </it>by evaluating the expression ranges of the corresponding genes. We then identified ten reactions in the metabolic network of <it>G. sulfurreducens </it>that are predicted to be candidates for regulation. We then compared the free energy ranges for these reactions with the corresponding gene expression fold changes under conditions of different environmental and genetic perturbations and show that the model predictions of regulation are consistent with data. In addition, we also identify reactions that operate close to equilibrium and show that the experimentally determined exchange coefficient (a measure of reversibility) is significant for these reactions.</p> <p>Conclusions</p> <p>Application of the thermodynamic constraints resulted in identification of potential bottleneck reactions not only from the central metabolism but also from the nucleotide and amino acid subsystems, thereby showing the highly coupled nature of the thermodynamic constraints. In addition, thermodynamic variability analysis serves as a valuable tool in estimating the ranges of Δ_rG' of every reaction in the model leading to the prediction of regulatory sites in the metabolic network, thereby characterizing the regulatory network in both a model organism such as <it>E. coli </it>as well as a non model organism such as <it>G. sulfurreducens</it>.</p

Realistic Anatomical Prostate Models for Surgical Skills Workshops Using Ballistic Gelatin for Nerve-Sparing Radical Prostatectomy and Fruit for Simple Prostatectomy

PURPOSE: Understanding of prostate anatomy has evolved as techniques have been refined and improved for radical prostatectomy (RP), particularly regarding the importance of the neurovascular bundles for erectile function. The objectives of this study were to develop inexpensive and simple but anatomically accurate prostate models not involving human or animal elements to teach the terminology and practical aspects of nerve-sparing RP and simple prostatectomy (SP). MATERIALS AND METHODS: The RP model used a Foley catheter with ballistics gelatin in the balloon and mesh fabric (neurovascular bundles) and balloons (prostatic fascial layers) on either side for the practice of inter- and intrafascial techniques. The SP model required only a ripe clementine, for which the skin represented compressed normal prostate, the pulp represented benign tissue, and the pith mimicked fibrous adhesions. A modification with a balloon through the fruit center acted as a "urethra." RESULTS: Both models were easily created and successfully represented the principles of anatomical nerve-sparing RP and SP. Both models were tested in workshops by urologists and residents of differing levels with positive feedback. CONCLUSIONS: Low-fidelity models for prostate anatomy demonstration and surgical practice are feasible. They are inexpensive and simple to construct. Importantly, these models can be used for education on the practical aspects of nerve-sparing RP and SP. The models will require further validation as educational and competency tools, but as we move to an era in which human donors and animal experiments become less ethical and more difficult to complete, so too will low-fidelity models become more attractive