Abstract: Problem statement: In only a few years, Multi-Protocol Label Switching (MPLS) has evolved from an exotic technology to a mainstream tool used by service providers to create revenue- generating services. MPLS provides a high reliable Label Switched Path (LSP). MPLS failures may degrade the reliability of the MPLS networks. Approach: For that reason, many studies have been conducted to keep the high reliability and survivability of the MPLS networks. Unlike User Datagram Protocol (UDP), TransmissionControlProtocol does not perform well in case of like-failure of MPLS networks because of its inability to distinguish packet loss due to link-failure. After the recovery time, TCP takes longer time than UDP to continue as it was before the failure. Results: In terms of packet loss, TCP performs better than UDP. However, the receiving rate of the TCP traffic is much worse than UDP traffic. A need for a mechanism to improve the behavior of TCP after a link failure is needed. This study focused on comparing the behavior of different types TCP as well as UDP traffic over MPLS networks in case of link, node or congestion failures. Conclusion: Although extensions of RSVP-TE protocol support fast recovery mechanism of MPLS networks, the behavior of TCP will be affected during recovery time much more than with UDP.
TransmissionControlProtocol (TCP) is a fundamental protocol in the TCP/IP Protocol Suite.TCP was well designed and optimized to work over wired networks where most packet loss occurs due to network congestion. In theory, TCP should not care whether it is running over wired networks, WLANs, or Mobile Ad hoc Networks (MANETs). In practice, it does matter because most TCP deployments have been carefully designed based on the assumption that congestion is the main factor of network instability. However, MANETs have other dominating factors that cause network instability. Forgetting the impact of these factors violates some design principles of TCP congestion control and open questions for future research to address. This study aims to introduce a model that shows the impact of MANET factors on TCP congestion control. To achieve this aim, Design Research Methodology (DRM) proposed by BLESSING was used as a guide to present this model. The proposed model describes the existing situation of TCP congestion control. Furthermore, it points to the factors that are most suitable to be addressed by researchers in order to improve TCP performance. This research proposes a novel model to present the impact of MANET factors on TCP congestion control. The model is expected to serve as a benchmark for any intended improvement and enhancement of TCP congestion control over MANET.
TCP responds to all losses by invoking congestion control and avoidance algorithms, resulting in degraded End-to-End performance in wireless environment. The TCP congestion control should be modified to utilize the available bandwidth efficiently in wireless environments. Shakya et al. (2013) in thesse networks,shared wireless channal and dnamic topology cause interference and fading during packet transmission.Packet loss and bandwidth variation are caused due to congestion. Therefore time and enaergy are wasted during during is recovery.The Enhanced TCP mechanism get improve result of TCP previous technique and eliminate the congestion from the network by analyzing various network parameter like throughput, packet delivery ratio, routing overhead,TCP packet analysis.The packet loss can be caused by congestion control over a mobility and failure adaptive routing protocol at the network layer (Sharma and Bhadauria, 2012). Ahmed et al. (2010), they identified that throughput redection in route change results in link disconnections. Mobile Adhoc Network have dynamic number of nodes connectivity in mobility. When the number of nodes is higher, DSR and TORA would be avoided and AODV has better throughput performance (Paul et al., 2012).
in a large number of insects and other arthropod species (Werren et al. 2008). Some Wolbachia strains are also described as symbionts of filarial nematodes that infect humans and cause diseases such as river blindness and elephantiasis (Bandi et al. 1998). However, there is cur- rently some controversy as to whether the Wolbachia that infect filarial nematodes should be classified as a sepa- rate species as their biology is quite distinct to the Wol- bachia that infect insects (Pfarr et al. 2007). Wolbachia are able to actively spread into insect populations by ma- nipulating insect reproduction (Werren et al. 2008). They are vertically transmitted across generations (via eggs) and confer reproductive advantages to infected females through a series of reproductive phenotypes that include cytoplasmic incompatibility, feminization, male killing or parthenogenesis (Werren et al. 2008). Wolbachia has long been considered as a potential biocontrol agent for insects and the pathogens they transmit, but has never been operationally deployed beyond pilot testing (Laven 1967, Beard et al. 1993, Sinkins & O’Neill 2000, Rasgon et al. 2003, Brownstein et al. 2003, Cook et al. 2007). Wolbachia as a biological control agent against mosquito-borne diseases
In todays wireless networks, stations using the IEEE 802.11 standard contend for the channel using the Distributed Coordination Function (DCF). Research has shown that DCF’s performance degrades especially with the large number of stations. This becomes more concerning due to the increasing proliferation of wireless devices. In this paper, we present a Medium Access Control (MAC) scheme for wireless LANs and compare its performance to DCF . Our scheme, which attempts to resolve the contention in a constant number of slots (or constant time), is called CONSTI. The contention resolution happens over a predefined number of slots. In a slot, the stations probabilistically send a jam signal on the channel. The stations listening retire if they hear a jam signal. The others continue to the next slot. Over several slots, we aim to have one station remaining in the contention, which will then transmit its data. We find the optimal parameters of CONSTI and present an analysis on its performance
Kone et al.  have developed QUORUM, a novel QoS-aware routing protocol for wireless mesh networks. Specifically, QUORUM takes three QoS metrics into account: bandwidth, end to end delay and route robustness. To optimize QUORUM for wireless mesh networks, they proposed several mechanisms for topology aware route discovery that drastically reduced the control overhead and network congestion from route discovery. In addition, they introduced the novel DUMMY-RREP data latency estimator and show it to be effective in providing accurate estimates of end-to- end delay experienced by data packets. Finally, their proposed link robustness metric allows QUORUM to punish and discourage free-riding behavior by selfish nodes.
The final presentation and overall summary was made by P Desjeux (Geneva, Switzerland), repre- senting the World Health Organization. Dr Desjeux thanked the workshop participants for raising awareness of the challenges posed by the chang- ing epidemiological situation of the New World leishmaniases. He stressed that research should continue on the characterization of complex zoonotic transmission cycles (both sylvatic and domestic), which continue to make control more challenging than for anthroponotic leishmaniasis diseases in other regions. The results of the few intervention trials presented in this workshop and elsewhere, however, offer sufficient encourage- ment to believe that cost-effective campaigns against domestic transmission of the New World leishmaniases are an achievable goal. International co-operation will be essential to achieving this aim; vectors and parasites cross national boundaries, and this workshop confirmed that experience from one country is often of great relevance to others within the region. The sharing of research findings, the
The simplest software approach for radio-wave prop- agation modeling at high frequencies (VHF to SHF) is semi-empirical, such as the well-known exponential path-loss model. Radiowave propagation models using detailed terrain databases are commonly referred as Site Specific Propagation models (SISP) . Smaller scenar- ios (usually indoors) may benefit from more complex and accurate approaches such as ray-tracing modeling. In this technique, the main propagation paths (rays) are de- terministically found based on the common electromag- netic phenomena of reflection, refraction, and scattering, which includes diffraction. Ray-tracing is usually carried out two-fold, using either greedy methods or image theory . With the ever growing available numerical capacity of computers, ray-tracing models have increas- ingly become more attractive as propagation prediction tools. Some researchers even expect that deterministic modeling may prevail in a near future, as the preferred approach for propagation prediction, even outdoors . Topology Control (TC) is the art of coordinating nodes’ decisions regarding their transmission ranges, in order to generate a network with the desired properties (e.g. connectivity) while reducing node energy consump- tion and/or increasing network capacity . A topology controlprotocol should have some basic properties: be fully distributed and asynchronous; be localized; gen- erate a topology that preserves the original network connectivity and relies, if possible, on bidirectional links; generate a topology with small physical degree; and rely on ’low-quality’ information . Usually, Distributed Topology Control Protocols (DTCPs) solutions use a bottom-up approach, such as CTBC  and KN EIGH - L EV  in which the sensor nodes start either from a lower transmission power level (TPL) up to a higher suitable TPL that often is more economic but takes longer to converge, or the transmitters start with higher TPLs (K-N EIGH , LSP  and XTC  stepping down to a suitable TPL, thus spending more power though converging faster.
The three main components in PON architectures are the Optical Line Terminal (OLT), the Optical Distribution Network (ODN), and the Optical Network Unit (ONU). These elements can be seen below in Figure 2.1. An OLT, which is located in a Central Office (CO), is connected through an optical fiber to one or more 1:N optical splitters. The OLT is used to control the data flow across the ODN, upstream and downstream, and provide services to the subscribed users. Each distributed fiber forwards these services towards an ONU, where the signal is further dispersed to all subscribers attached to this ONU. Initially, the downstream services were mostly videos, so the upstream channels were usually of lower data rates. Lately, with the surge of cloud services, gaming, and streaming, the upstream bandwidth is more requested, and newer technologies have a symmetric relationship between download and upload. An ONU can also be called an Optical Network Terminal (ONT), if it is located inside the client’s premises [7, 9, 12, 13, 14].
Brucellosis is a bacterial disease caused by brucella; mainly spread by direct contact transmission through the brucella carriers, or indirect contact transmission by the environment containing large quantities of bacteria discharged by the infected individuals. At the beginning of 21st century, the epidemic among dairy cows in Zhejiang province, began to come back and has become a localized prevalent epidemic. Combining the pathology of brucellosis, the reported positive data characteristics, and the feeding method in Zhejiang province, this paper establishes an SEIV dynamic model to excavate the internal transmission dynamics, fit the real disease situation, predict brucellosis tendency and assess control measures in dairy cows. By careful analysis, we give some quantitative results as follows. (1) The external input of dairy cows from northern areas may lead to high fluctuation of the number of the infectious cows in Zhejiang province that can reach several hundreds. In this case, the disease cannot be controlled and the infection situation cannot easily be predicted. Thus, this paper encourages cows farms to insist on self-supplying production of the dairy cows. (2) The effect of transmission rate of brucella in environment to dairy cattle on brucellosis spreading is greater than transmission rate of the infectious dairy cattle to susceptible cattle. The prevalence of the epidemic is mainly aroused by environment transmission. (3) Under certain circumstances, the epidemic will become a periodic phenomenon. (4) For Zhejiang province, besides measures that have already been adopted, sterilization times of the infected regions is suggested as twice a week, and should be combined with management of the birth rate of dairy cows to control brucellosis spread.
Funding: This work was funded in part by the Bill & Melinda Gates Foundation through award numbers 45114 (Malaria Transmission Consortium), 51431 (Replacing DDT: Rigorous Evaluation of Spatial Repellents for the Control of Vector Borne Diseases), 52644 (Control of Anophelines by the auto-dissemination of insecticides) and 39777.01 (A stochastic simulation platform for predicting the effects of different malaria intervention strategies). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. No additional external funding was received for this study. Competing Interests: While this study was independently funded by the Bill & Melinda Gates Foundation, two of the authors have received funding support for other research projects from manufacturers of insecticidal public health products: Vestergaard Frandsen SA (GFK), Syngenta (SJM), Pinnacle Development (SJM) and SC Johnson (SJM). This does not alter the authors’ adherence to all the PLoS ONE policies on sharing data and materials.
To compare rates of clinical case prevention and overtreatment across HFCAs, we normal- ized populations to 1000 people and fixed coverage at 80%, a high but achievable rate (Fig 4B). Because transmission was so low in Gwembe HFCA, any mass campaign would avert only a handful of clinical cases: MSAT averted on average two clinical cases and MDA averted five, with the remaining infection detection strategies falling in between. Yet an MDA campaign would result in treating over 700 people who were uninfected, and those individuals derived lit- tle benefit from prophylactic effects given the low rate of transmission. Within-household fMDA, the infection-detection strategy that resulted in the least overtreatment next to MSAT, required overtreatment of nearly 50 individuals to avert less than one clinical case. These high rates of overtreatment suggested that MSAT might be the only reasonable option for mass treatment for malaria control in low-prevalence areas despite MSAT’s relative inability to deplete the infectious reservoir.
As seen before, applications dealing with real life indicators or in fact dealing with real life data, often values distributability and scalability. Using the inter-connectivity offered by the proliferation of the Internet, users can be ever closer to each other, allowing their data to be shared amongst each other and creating services that facilitate this is becoming an ever growing market. For this project the Application to be developed will seek that end and create an API that will aid these data transactions, leaving the developers to worry with other issues. The API will use techniques that have proven themselves and create a web service that interconnects several components namely server, database and the API itself. In this case the nature of the data being transferred involves small, asynchronous messages that do not required specific protocols and are transmited at an irregular pace. As such both Node.js and web sockets are evaluated for, above all, they offer a lightweight infrastructure that values speed and are able to handle erratic messaging times. Node.js is an asynchronous event-driven framework for web applications that favours these types of messaging patterns and web socket is communication protocol that simulates the behaviour of sockets through the internet, i.e. a one to one direct connection.
A evolução do Programa Brasileiro se refletiu na abrangência da sua representatividade dentro do universo corporati- vo nacional. Em 2010, o Programa já reunia 39 membros; no ano seguinte, saltou para 78; e em 2013 chega a marca de 106 organizações membro. Mais do que apoiar a elaboração de inventários corporativos, o Programa Brasileiro GHG Protocol passou a observar outros desafios enfrentados por governos e empresas na gestão e redução das suas emissões de GEE.
The seventh chapter is a listing of the rights and duties of the shareholders, concerning the strict confidentiality of information, the prohibited use of the brand and commercial name, the providing of services by a family member’s firm at market rates and the exclusivity agreement. The general rules of the protocol are established in the eight chapter and allow changes to the protocol if all the signatories are in agreement to the proposal. Every two years, the family protocol is supposed to be revised. The protocol is exclusive to the family and rules over conflicting opinions, except legal obligations, to which the protocol is also undermined. These two chapters follow standard necessary procedures and frameworks, serving as pillars for the family-specific content-rich sections to be fully integrated.