FTP Download Research Articles

Analyzing TCP Performance in High Bit Error Rate Using Simulation and Modeling

While Transmission Control Protocol (TCP) works well with a low bit error rate (BER), the performance of TCP degrades significantly if the BER rises above a certain level. A study of the performance of TCP with high BER is required for the efficient design and deployment of such systems. In this paper, we address the problem of TCP performance in high BERs and analyze the issues by investigating the effect of BERs on system performance. We consider TCP Reno in our study to explore the system performance using extensive analysis of simulation and modeling. In the analysis, we consider the amount of datagram sent and retransmitted, mean throughput, link-layer overhead, TCP window size, FTP download response time, packet dropping and retransmission, and the TCP congestion avoidance mechanism. We validate simulation results by setting up a virtualized testbed using Linux hosts and a Linux router. The results obtained show that TCP throughput degrades significantly and eventually collapses at the packet drop probability of 10% (BER = 10−5). The FTP download response time is about 32 times longer than that of a perfect channel (no packet dropping). We found that TCP Reno cannot handle such a high BER to operate in wireless environments effectively. Finally, we provide recommendations for network researchers and engineers confronted with the challenge of operating TCP over noisy channels.

Design and implementation of a speed test system for campus network based on IPv6

In order to realize the end-to-end network speed measurement in the campus network and solve the problem that the current speed measurement system is not well adapted for IPv6 campus network, we adopt the C/S mode to build a software for the client/server ends distributed in the selective target area. For end-to-end testing, the software provides various methods of network speed measurement including FTP download, and provides current network speed measurement data. We also design network quality classification standards, and evaluate current network conditions according to them. At the same time, our software can do the speed measurement for localized download service of high-quality resources.

STRSeq: A catalog of sequence diversity at human identification Short Tandem Repeat loci

The STR Sequencing Project (STRSeq) was initiated to facilitate the description of sequence-based alleles at the Short Tandem Repeat (STR) loci targeted in human identification assays. This international collaborative effort, which has been endorsed by the ISFG DNA Commission, provides a framework for communication among laboratories. The initial data used to populate the project are the aggregate alleles observed in targeted sequencing studies across four laboratories: National Institute of Standards and Technology (N=1786), Kings College London (N=1043), University of North Texas Health Sciences Center (N=839), and University of Santiago de Compostela (N=944), for a total of 4612 individuals. STRSeq data are maintained as GenBank records at the U.S. National Center for Biotechnology Information (NCBI), which participates in a daily data exchange with the DNA DataBank of Japan (DDBJ) and the European Nucleotide Archive (ENA). Each GenBank record contains the observed sequence of a STR region, annotation (“bracketing”) of the repeat region and flanking region polymorphisms, information regarding the sequencing assay and data quality, and backward compatible length-based allele designation. STRSeq GenBank records are organized within a BioProject at NCBI (https://www.ncbi.nlm.nih.gov/bioproject/380127), which is sub-divided into: commonly used autosomal STRs, alternate autosomal STRs, Y-chromosomal STRs, and X-chromosomal STRs. Each of these categories is further divided into locus-specific BioProjects. The BioProject hierarchy facilitates access to the GenBank records by browsing, BLAST searching, or ftp download. Future plans include user interface tools at strseq.nist.gov, a pathway for submission of additional allele records by laboratories performing population sample sequencing and interaction with the STRidER web portal for quality control (http://strider.online).

A global water resources ensemble of hydrological models: the eartH2Observe Tier-1 dataset

Abstract. The dataset presented here consists of an ensemble of 10 global hydrological and land surface models for the period 1979–2012 using a reanalysis-based meteorological forcing dataset (0.5° resolution). The current dataset serves as a state of the art in current global hydrological modelling and as a benchmark for further improvements in the coming years. A signal-to-noise ratio analysis revealed low inter-model agreement over (i) snow-dominated regions and (ii) tropical rainforest and monsoon areas. The large uncertainty of precipitation in the tropics is not reflected in the ensemble runoff. Verification of the results against benchmark datasets for evapotranspiration, snow cover, snow water equivalent, soil moisture anomaly and total water storage anomaly using the tools from The International Land Model Benchmarking Project (ILAMB) showed overall useful model performance, while the ensemble mean generally outperformed the single model estimates. The results also show that there is currently no single best model for all variables and that model performance is spatially variable. In our unconstrained model runs the ensemble mean of total runoff into the ocean was 46 268 km3 yr−1 (334 kg m−2 yr−1), while the ensemble mean of total evaporation was 537 kg m−2 yr−1. All data are made available openly through a Water Cycle Integrator portal (WCI, wci.earth2observe.eu), and via a direct http and ftp download. The portal follows the protocols of the open geospatial consortium such as OPeNDAP, WCS and WMS. The DOI for the data is https://doi.org/10.1016/10.5281/zenodo.167070.

FAQ-MAST TCP for Secure Download

The innovative congestion control algorithm named FAQ-MAST TCP (Fast Active Queue Management Stability Transmission Control Protocol) is aimed for high-speed long-latency networks. Four major difficulties in FAQ-MAST TCP are highlighted at both packet and flow levels. The architecture and characterization of equilibrium and stability properties of FAQ-MAST TCP are discussed. Experimental results are presented comparing the first Linux prototype with TCP Reno, HSTCP, and STCP in terms of throughput, fairness, stability, and responsiveness. FAQ-MAST TCP aims to rapidly stabilize high-speed long-latency networks into steady, efficient and fair operating points, in dynamic sharing environments, and the preliminary results are produced as output of our project. The Proposed architecture is explained with the help of an existing real-time example as to explain why FAQ-MAST TCP download is chosen rather than FTP download. The Paper is concluded with the results of the new congestion control algorithm aided with the graphs obtained during its simulation in NS2.

Analysis of Link State Resource Reservation Protocol for Congestion Management in Smart Web Hotspot Environments

With the wide spread of WiFi hotspots, concentrated traffic workload on Smart Web (SW) can slow down the network performance. This paper presents a congestion management strategy considering real time activities in today’s smart web. With the SW context, cooperative packet recovery using resource reservation procedure for TCP flows was adapted for mitigating packet losses. This is to maintain data consistency between various access points of smart web hotspot. Using a real world scenario, it was confirmed that generic TCP cannot handle traffic congestion in a SW hotspot network. With TCP in scalable workload environments, continuous packet drops at the event of congestion remains obvious. This is unacceptable for mission critical domains. An enhanced Link State Resource Reservation Protocol (LSRSVP) which serves as dynamic feedback mechanism in smart web hotspots is presented. The contextual behaviour was contrasted with the generic TCP model. For the LS-RSVP, a simulation experiment for TCP connection between servers at the remote core layer and the access layer was carried out while using selected benchmark metrics. From the results, under realistic workloads, a steady-state throughput response was achieved by TCP LS-RSVP to about 3650Bits /secs compared with generic TCP plots in a previous study. Considering network service availability, this was found to be dependent on fault-tolerance of the hotspot network. From study, a high peak threshold of 0.009 (i.e. 90%) was observed. This shows fairly acceptable service availability behaviour compared with the existing TCP schemes. For packet drop effects, an analysis on the network behaviour with respect to the LS-RSVP yielded a drop response of about 0.000106 bits/sec which is much lower compared with the case with generic TCP with over 0.38 bits/sec. The latency profile of average FTP download response was found to be 0.030secs, but with that of FTP upload response, this yielded about 0.028 sec. The results from the study demonstrate efficiency and optimality for realistic loads in Smart web contexts.

Computational clustering for viral reference proteomes.

The enormous number of redundant sequenced genomes has hindered efforts to analyze and functionally annotate proteins. As the taxonomy of viruses is not uniformly defined, viral proteomes pose special challenges in this regard. Grouping viruses based on the similarity of their proteins at proteome scale can normalize against potential taxonomic nomenclature anomalies. We present Viral Reference Proteomes (Viral RPs), which are computed from complete virus proteomes within UniProtKB. Viral RPs based on 95, 75, 55, 35 and 15% co-membership in proteome similarity based clusters are provided. Comparison of our computational Viral RPs with UniProt's curator-selected Reference Proteomes indicates that the two sets are consistent and complementary. Furthermore, each Viral RP represents a cluster of virus proteomes that was consistent with virus or host taxonomy. We provide BLASTP search and FTP download of Viral RP protein sequences, and a browser to facilitate the visualization of Viral RPs. http://proteininformationresource.org/rps/viruses/ chenc@udel.edu Supplementary data are available at Bioinformatics online.

OMIM.org: Online Mendelian Inheritance in Man (OMIM®), an online catalog of human genes and genetic disorders.

Online Mendelian Inheritance in Man, OMIM®, is a comprehensive, authoritative and timely research resource of curated descriptions of human genes and phenotypes and the relationships between them. The new official website for OMIM, OMIM.org (http://omim.org), was launched in January 2011. OMIM is based on the published peer-reviewed biomedical literature and is used by overlapping and diverse communities of clinicians, molecular biologists and genome scientists, as well as by students and teachers of these disciplines. Genes and phenotypes are described in separate entries and are given unique, stable six-digit identifiers (MIM numbers). OMIM entries have a structured free-text format that provides the flexibility necessary to describe the complex and nuanced relationships between genes and genetic phenotypes in an efficient manner. OMIM also has a derivative table of genes and genetic phenotypes, the Morbid Map. OMIM.org has enhanced search capabilities such as genome coordinate searching and thesaurus-enhanced search term options. Phenotypic series have been created to facilitate viewing genetic heterogeneity of phenotypes. Clinical synopsis features are enhanced with UMLS, Human Phenotype Ontology and Elements of Morphology terms and image links. All OMIM data are available for FTP download and through an API. MIMmatch is a novel outreach feature to disseminate updates and encourage collaboration.

FASTRA Safe and Secure

The innovative congestion control algorithm named FASTRA (Fast Active Stability TCP) is aimed for high-speed long-latency networks. Four major difficulties in FASTRA are highlighted at both packet and flow levels. The architecture and characterization of equilibrium and stability properties of FASTRA are robust. Experimental results of FASTRA outsmart TCP Reno, HSTCP, and STCP in terms of throughput, fairness, stability, and responsiveness. FASTRA aims to rapidly stabilize high-speed long-latency networks into steady, efficient and fair operating points, in dynamic sharing environments, and the preliminary results are produced as output of our project. The Proposed architecture is explained with the help of an existing real-time example as to explain why FASTRA download is chosen rather than FTP download. The Paper is concluded with the results of the new congestion control algorithm aided with the graphs obtained during its simulation in NS2. On proper implementation, many safe, FASTRA downloads and data transfers can be carried over a high speed internet network.

Dynamic Routing Protocols Analysis based on Dissimilar Number of Packets

Efficient routing is one of the key challenges in the design and performance of a large scale intra- domain network. This paper describes the analysis of dynamic routing protocols IS-IS,IGRP,RIP for the scenario which has fifty number of workstations working on three dissimilar applications(Ftp, Remote Login and Videoconferencing) based on increasing number of packets per sec sent. High speed network is the demand of the user in order to perform multiple tasks with reliability so that its performance is efficient that is why we opted for dissimilar number of packets varying from hundred to thousand and analyzed their effects in the performance of LAN. Simulation is carried out with the help of Optimized Networking Engineering Tool (OPNET) which gives the better edge over the other network simulation tools available. The assessment is based on two parameters namely Ftp Download Response Time and Ftp Upload Response Time. The results concluded that that overall best performance can be achieved with the help of IS-IS protocol other than RIP and IGRP for increasing number of packets in the given scenario and hence it is observed that by sending maximum number of packets there is speed enhancement in the given network with high efficiency.

FAQ-MAST TCP for Secure Download

The innovative congestion control algorithm named FAQ-MAST TCP (Fast Active Queue Management Stability Transmission Control Protocol) is aimed for high-speed long-latency networks. Four major difficulties in FAQ-MAST TCP are highlighted at both packet and flow levels. The architecture and characterization of equilibrium and stability properties of FAQ-MAST TCP are discussed. Experimental results are presented comparing the first Linux prototype with TCP Reno, HSTCP, and STCP in terms of throughput, fairness, stability, and responsiveness. FAQ-MAST TCP aims to rapidly stabilize high-speed long-latency networks into steady, efficient and fair operating points, in dynamic sharing environments, and the preliminary results are produced as output of our project. The Proposed architecture is explained with the help of an existing real-time example as to explain why FAQ-MAST TCP download is chosen rather than FTP download. The Paper is concluded with the results of the new congestion control algorithm aided with the graphs obtained during its simulation in NS2.

QoS aware dynamic route optimization for Proxy Mobile IPv6 networks

AbstractProxy Mobile IPv6 is a network based mobility management solution and was proposed to address the shortcomings of the existing set of mobility management protocols. The presence of local mobility anchors (LMA) in PMIPv6 networks can lead constrained routing and create areas of bottleneck. This is due to all traffic to the mobile nodes (MNs) in the PMIPv6 domain having to flow to and from the LMA. Future IP networks will support a wide variety of sessions ranging for high QoS Video conferencing to FTP and P2P download. Providing the same level of mobility support for all of these sessions can lead to the resources of LMA being drained. To avoid this, we propose the QoS aware Dynamic Route Optimization scheme where the network identifies the lower QoS sessions and establishes a binding update with the correspondant node (CN) rather than with the LMA. To achieve this a flow based binding approach is followed. The level of congestion in the network is also considered as part of the mechanism. To ensure optimal performance of the proposed mechanism, routing policies are proposed. Simulation results show considerable benefit to the network in terms of reduction in blocking probability as well as reduction in tunnelling overhead cost in comparisons to no route optimization (RO) and adaptive route optimization (ARO) being deployed in the PMIPv6 networks. Copyright © 2009 John Wiley & Sons, Ltd.

Global Bathymetry and Elevation Data at 30 Arc Seconds Resolution: SRTM30_PLUS

A new 30-arc second resolution global topography/bathymetry grid (SRTM30_PLUS) has been developed from a wide variety of data sources. Land and ice topography comes from the SRTM30 and ICESat topography, respectively. Ocean bathymetry is based on a new satellite-gravity model where the gravity-to-topography ratio is calibrated using 298 million edited soundings. The main contribution of this study is the compilation and editing of the raw soundings, which come from NOAA, individual scientists, SIO, NGA, JAMSTEC, IFREMER, GEBCO, and NAVOCEANO. The gridded bathymetry is available for ftp download in the same format as the 33 tiles of SRTM30 topography. There are 33 matching tiles of source identification number to convey the provenance of every grid cell. The raw sounding data, converted to a simple common format, are also available for ftp download.

Thesaurus musicarum latinarum (review)

Thesaurus musicarum latinarum. Thomas J. Mathiesen, Project Director. Center for the History of Music Theory and Literature, Indiana University. http://www.music.indiana.edu/tml/. [Requires a Web browser and Internet connection.] It was with great interest and enthusiasm that I accepted the task of reviewing the Thesaurus musicarum latinarum (TML) for Notes. As a medieval musicologist in his second career as a working librarian, I remember when TML first appeared on the scene, back when FTP and listserv were the dominant means of accessing files over the Internet (well before browsers made their appearance). It was both exciting and exhilarating to be able to participate in one of the first music consortiums, where the effort was done by working musicologists, the content was freely available through FTP download, and one could get regular updates on the progress and content of the project through e-mail. Now, in this Internet environment where Web pages and Web sites are more common and convenient than FTP download and Veronica (remember her?!), TML continues to move forward as a pioneer in the area of music on the Web, and in the continuing development of global participation by the music community to provide open access to this unique and otherwise hard-to-acquire material. As the Web site states, TML is an evolving database of the entire corpus of Latin music theory written during the Middle Ages and the As such, it fills a huge gap for scholars in these areas of study, by 1) providing access to these materials in one location, and 2) providing it for free. Other databases with this kind of depth of content and scholarship entail annual expenditure on the part of libraries in order to provide access for their patrons. The goals of TML are immediately apparent when one accesses the Web site. Instead of going immediately to database content, or the actual front page of the Web site, the user is taken to a copyright notice, where it is made clear that everything is either public domain or from copyrighted materials for which TML has obtained permission. In addition, the publishers make clear that they do claim copyright on content created by TML staff (introduction, canon, text and graphics, the encoding system, and the compilation of the sources). Once the user enters the Web site, it is readily apparent that the project is under the direction of the Center for the History of Music Theory and Literature at Indiana University, and that Thomas J. Mathiesen is the director. The introduction to TML describes what it is, as well as other projects and databases that it complements but does not duplicate. These other projects include: the Thesaurus Linguae Graecae (http://www.tlg.uci.edu/), the Lexicon musicum Latinum medii aevi (http://www.lml.badw.de/), the Thesaurus Linguae Latinae (http://www.thesaurus.badw.de/), Saggi musicali italiani (http://www.music.indiana.edu/smi/), and the Center for the Computer Analysis of Texts (http://ccat.sas.upenn.edu/teachtech/about-ccat.html). The introduction also states the two fundamentals of the project since its beginning: that users be able to locate and retrieve sources without editorial intrusions (even those that correct errors); and that every printed edition of a particular text be available for users, even if it has been replaced by a more modern edition. The content of the database itself comprises Latin texts related in some way to music theory and composition in the Middle Ages and Renaissance. Most of our understanding of practical matters related to musical composition during these eras comes from these manuscripts; in fact, without these treatises, modern musicologists would have no idea when compositional techniques became standard practice. These treatises were often written by well-known musicians of the time, or by Latin scholars describing and defining current compositional and notational practices. The sources, while mainly Latin, come from all over Western Europe. …

XML — an opportunity for data standards in the geosciences

Extensible markup language (XML) is a recently introduced meta-language standard on the Web. It provides the rules for development of metadata (markup) standards for information transfer in specific fields. XML allows development of markup languages that describe what information is rather than how it should be presented. This allows computer applications to process the information in intelligent ways. In contrast hypertext markup language (HTML), which fuelled the initial growth of the Web, is a metadata standard concerned exclusively with presentation of information. Besides its potential for revolutionizing Web activities, XML provides an opportunity for development of meaningful data standards in specific application fields. The rapid endorsement of XML by science, industry and e-commerce has already spawned new metadata standards in such fields as mathematics, chemistry, astronomy, multi-media and Web micro-payments. Development of XML-based data standards in the geosciences would significantly reduce the effort currently wasted on manipulating and reformatting data between different computer platforms and applications and would ensure compatibility with the new generation of Web browsers. This paper explores the evolution, benefits and status of XML and related standards in the more general context of Web activities and uses this as a platform for discussion of its potential for development of data standards in the geosciences. Some of the advantages of XML are illustrated by a simple, browser-compatible demonstration of XML functionality applied to a borehole log dataset. The XML dataset and the associated stylesheet and schema declarations are available for FTP download.