Mitigating Network Service Disruptions in High-bandwidth, Intermittently Connected, and Peer-to-Peer Networks

Users demand high-bandwidth, ubiquitous and low-cost network services. This demand has pushed ISPs and application providers to offer more bandwidth, allow users to access the Internet almost everywhere, and provide cheap or free network services using peer-to-peer networks. These three trends underlie the growing success of today's Internet. However, (1) high-bandwidth can empower more effective denial-of-service attacks; (2) Internet access is widespread, but still not ubiquitous; and (3) peer-to-peer network services need to solve the service discovery problem. This thesis addresses these three challenges. First, we tackle denial-of-service attacks. The high bandwidth available in many parts of the Internet allows denial-of-service attacks to be effective, and the large scale of the Internet makes detecting and preventing these attacks difficult. Anonymity and openness of the Internet worsens this problem because anyone can send anything to anybody. To prevent these denial-of-service attacks, we propose Permission-Based-Sending (PBS), a signaling architecture for network traffic authorization. PBS uses the explicit permission to give legitimate users the authority to send packets. Signaling is used to configure this permission in the data path. This signaling approach enables easy installation for granting authorization to flows, and allows PBS to be deployed in existing networks. In addition, a monitoring mechanism provides a second line of defense against attacks. Next, we strive to make Internet access more ubiquitous. When public transportation stations have access points to provide Internet access to passengers, public transportation becomes a more attractive travel and commute option. However, the Internet connectivity is intermittent because passengers can access the Internet only when a bus or train is within the networking coverage of an AP at a stop. To efficiently handle this intermittent network for the public transit system, we develop Internet Cache on Wheels (ICOW), a system that provides a low-cost way for bus and train operators to offer access to Internet content. Each bus and train car is equipped with a smart cache that serves popular content to passengers. The cache updates its content based on passenger requests when it is within range of Internet access points placed at bus stops, train stations or depots. This aggregated Internet access is significantly more efficient than having passengers contact Internet access points individually and ensures continuous availability of content throughout the journey. Finally, we consider peer-to-peer services. Typical service discovery mechanisms in peer-to-peer networks cause significant overhead, consuming energy and bandwidth: (1) in highly mobile networks, service discovery consumes the energy of mobile devices to discover services that newly joined members provide; and (2) peer-to-peer network systems consumes bandwidth during service discovery. To resolve and analyze these service discovery problems, (1) we design an efficient service discovery mechanism that reduces energy consumption of mobile devices; and (2) we evaluate the bandwidth consumption caused by service discovery in real-world peer-to-peer networks

PBS: Signaling Architecture for Network Traffic Authorization

We present a signaling architecture for network traffic authorization, Permission-Based Sending (PBS). This architecture aims to prevent Denial-of-Service (DoS) attacks and other forms of unauthorized traffic. Towards this goal, PBS takes a hybrid approach: a proactive approach of explicit permissions and a reactive approach of monitoring and countering attacks. On-path signaling is used to configure the permission state stored in routers for a data flow. The signaling approach enables easy installation and management of the permission state, and its use of soft-state improves robustness of the system. For secure permission state setup, PBS provides security for signaling in two ways: signaling messages are encrypted end-to-end using public key encryption and TLS provides hop-by-hop encryption of signaling paths. In addition, PBS uses IPsec for data packet authentication. Our analysis and performance evaluation show that PBS is an effective and scalable solution for preventing various kinds of attack scenarios, including Byzantine attacks

Measurements of Multicast Service Discovery in a Campus

Applications utilizing multicast service discovery protocols, such as iTunes, have become increasingly popular. However, multicast service discovery protocols are considered to generate network traffic overhead, especially in a wireless network. Therefore, it becomes important to evaluate the traffic and overhead caused by multicast service discovery packets in real-world networks. We measure and analyze the traffic of one of the mostly deployed multicast service discovery protocols, multicast DNS (mDNS) service discovery, in a campus wireless network that forms a single multicast domain of large users. We also analyze different service discovery models in terms of packet overhead and service discovery delay under different network sizes and churn rates. Our measurement shows that mDNS traffic consumes about 13 percent of the total bandwidth

Accelerating Service Discovery in Ad-Hoc Zero Configuration Networking

Zero Configuration Networking (Zeroconf) assigns IP addresses and host names, and discovers service without a central server. Zeroconf can be used in wireless mobile ad-hoc networks which are based on IEEE 802.11 and IP. However, Zeroconf has problems in mobile ad-hoc networks as it cannot detect changes in the network topology. In highly mobile networks, Zeroconf causes network overhead while discovering new services. In this paper, we propose an algorithm to accelerate service discovery for mobile ad-hoc networks. Our algorithm involves the monitoring of network interface changes that occur when a device with IEEE 802.11 enabled joins a new network area. This algorithm allows users to discover network topology changes and new services in real-time while minimizing network overhead

Bucillamine prevents cisplatin-induced ototoxicity through induction of glutathione and antioxidant genes.

Bucillamine is used for the treatment of rheumatoid arthritis. This study investigated the protective effects of bucillamine against cisplatin-induced damage in auditory cells, the organ of Corti from postnatal rats (P2) and adult Balb/C mice. Cisplatin increases the catalytic activity of caspase-3 and caspase-8 proteases and the production of free radicals, which were significantly suppressed by pretreatment with bucillamine. Bucillamine induces the intranuclear translocation of Nrf2 and thereby increases the expression of γ-glutamylcysteine synthetase (γ-GCS) and glutathione synthetase (GSS), which further induces intracellular antioxidant glutathione (GSH), heme oxygenase 1 (HO-1) and superoxide dismutase 2 (SOD2). However, knockdown studies of HO-1 and SOD2 suggest that the protective effect of bucillamine against cisplatin is independent of the enzymatic activity of HO-1 and SOD. Furthermore, pretreatment with bucillamine protects sensory hair cells on organ of Corti explants from cisplatin-induced cytotoxicity concomitantly with inhibition of caspase-3 activation. The auditory-brainstem-evoked response of cisplatin-injected mice shows marked increases in hearing threshold shifts, which was markedly suppressed by pretreatment with bucillamine in vivo. Taken together, bucillamine protects sensory hair cells from cisplatin through a scavenging effect on itself, as well as the induction of intracellular GSH

A Wearable Wrist Band-Type System for Multimodal Biometrics Integrated with Multispectral Skin Photomatrix and Electrocardiogram Sensors

Multimodal biometrics are promising for providing a strong security level for personal authentication, yet the implementation of a multimodal biometric system for practical usage need to meet such criteria that multimodal biometric signals should be easy to acquire but not easily compromised. We developed a wearable wrist band integrated with multispectral skin photomatrix (MSP) and electrocardiogram (ECG) sensors to improve the issues of collectability, performance and circumvention of multimodal biometric authentication. The band was designed to ensure collectability by sensing both MSP and ECG easily and to achieve high authentication performance with low computation, efficient memory usage, and relatively fast response. Acquisition of MSP and ECG using contact-based sensors could also prevent remote access to personal data. Personal authentication with multimodal biometrics using the integrated wearable wrist band was evaluated in 150 subjects and resulted in 0.2% equal error rate ( EER ) and 100% detection probability at 1% FAR (false acceptance rate) ( PD.1 ), which is comparable to other state-of-the-art multimodal biometrics. An additional investigation with a separate MSP sensor, which enhanced contact with the skin, along with ECG reached 0.1% EER and 100% PD.1 , showing a great potential of our in-house wearable band for practical applications. The results of this study demonstrate that our newly developed wearable wrist band may provide a reliable and easy-to-use multimodal biometric solution for personal authentication

Castanea crenata honey reduces influenza infection by activating the innate immune response

Influenza is an acute respiratory disorder caused by the influenza virus and is associated with prolonged hospitalization and high mortality rates in older individuals and chronically ill patients. Vaccination is the most effective preventive strategy for ameliorating seasonal influenza. However, the vaccine is not fully effective in cases of antigenic mismatch with the viral strains circulating in the community. The emergence of resistance to antiviral drugs aggravates the situation. Therefore, developing new vaccines and antiviral drugs is essential. Castanea crenata honey (CH) is an extensively cultivated food worldwide and has been used as a nutritional supplement or herbal medicine. However, the potential anti-influenza properties of CH remain unexplored. In this study, the in vitro and in vivo antiviral effects of CH were assessed. CH significantly prevented influenza virus infection in mouse Raw264.7 macrophages. CH pretreatment inhibited the expression of the viral proteins M2, PA, and PB1 and enhanced the secretion of proinflammatory cytokines and type-I interferon (IFN)-related proteins in vitro. CH increased the expression of RIG-1, mitochondrial antiviral signaling (MAVS) protein, and IFN-inducible transmembrane protein, which interferes with virus replication. CH reduced body weight loss by 20.9%, increased survival by 60%, and decreased viral replication and inflammatory response in the lungs of influenza A virus-infected mice. Therefore, CH stimulates an antiviral response in murine macrophages and mice by preventing viral infection through the RIG-1-mediated MAVS pathway. Further investigation is warranted to understand the molecular mechanisms involved in the protective effects of CH on influenza virus infection

Enhancing the immunogenicity of tumour lysate-loaded dendritic cell vaccines by conjugation to virus-like particles

BACKGROUND: Tumour cell lysates are an excellent source of many defined and undefined tumour antigens and have been used clinically in immunotherapeutic regimes but with limited success. METHODS: We conjugated Mel888 melanoma lysates to rabbit haemorrhagic disease virus virus-like particles (VLP), which can act as vehicles to deliver multiple tumour epitopes to dendritic cells (DC) to effectively activate antitumour responses. RESULTS: Virus-like particles did not stimulate the phenotypic maturation of DC although, the conjugation of lysates to VLP (VLP-lysate) did overcome lysate-induced suppression of DC activation. Lysate-conjugated VLP enhanced delivery of antigenic proteins to DC, while the co-delivery of VLP-lysates with OK432 resulted in cross-priming of naïve T cells, with expansion of a MART1(+) population of CD8(+) T cells and generation of a specific cytotoxic response against Mel888 tumour cell targets. The responses generated with VLP-lysate and OK432 were superior to those stimulated by unconjugated lysate with OK432. CONCLUSION: Collectively, these results show that the combination of VLP-lysate with OK432 delivered to DC overcomes the suppressive effects of lysates, and enables priming of naïve T cells with superior ability to specifically kill their target tumour cells

Study protocol for the translating research in elder care (TREC): building context – an organizational monitoring program in long-term care project (project one)

<p>Abstract</p> <p>Background</p> <p>While there is a growing awareness of the importance of organizational context (or the work environment/setting) to successful knowledge translation, and successful knowledge translation to better patient, provider (staff), and system outcomes, little empirical evidence supports these assumptions. Further, little is known about the factors that enhance knowledge translation and better outcomes in residential long-term care facilities, where care has been shown to be suboptimal. The project described in this protocol is one of the two main projects of the larger five-year Translating Research in Elder Care (TREC) program.</p> <p>Aims</p> <p>The purpose of this project is to establish the magnitude of the effect of organizational context on knowledge translation, and subsequently on resident, staff (unregulated, regulated, and managerial) and system outcomes in long-term care facilities in the three Canadian Prairie Provinces (Alberta, Saskatchewan, Manitoba).</p> <p>Methods/Design</p> <p>This study protocol describes the details of a multi-level – including provinces, regions, facilities, units within facilities, and individuals who receive care (residents) or work (staff) in facilities – and longitudinal (five-year) research project. A stratified random sample of 36 residential long-term care facilities (30 urban and 6 rural) from the Canadian Prairie Provinces will comprise the sample. Caregivers and care managers within these facilities will be asked to complete the TREC survey – a suite of survey instruments designed to assess organizational context and related factors hypothesized to be important to successful knowledge translation and to achieving better resident, staff, and system outcomes. Facility and unit level data will be collected using standardized data collection forms, and resident outcomes using the Resident Assessment Instrument-Minimum Data Set version 2.0 instrument. A variety of analytic techniques will be employed including descriptive analyses, psychometric analyses, multi-level modeling, and mixed-method analyses.</p> <p>Discussion</p> <p>Three key challenging areas associated with conducting this project are discussed: sampling, participant recruitment, and sample retention; survey administration (with unregulated caregivers); and the provision of a stable set of study definitions to guide the project.</p