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Description: ORAU conducted confirmatory surveys of the Hematite site during the period of June 12 through June 13, 2012. The survey activities included in-process inspections, document review, walkover surveys, sampling activities, and laboratory analysis of split samples. WEC was forthcoming with information relating to practices, procedures, and surface scan results. Scans performed by the WEC technician were extremely thorough and methodical. The WEC and ORAU technicians identified the same areas of elevated activity with comparable detector responses. WEC sampling of re-use soils, waste soils, sediments, and groundwater were conducted under ORAU observation. The sampling efforts observed by ORAU were performed in accordance with site-specific procedures and in a manner sufficient to provide quality supporting data. Three observations were made during groundwater sampling activities. First, the water level indicator was re-used without submitting rinse blank. Second, bubbles created during tubing extraction could indicate the presence of volatilized organic compounds. Third, samplers did not use a photo ionization detector prior to sample collection to indicate the presence of volatile organic vapors. Results of split samples indicated a high level of comparability between the WEC and ORAU/ORISE radiological laboratories. Analytical practices and procedures appear to be sufficient in providing quality radiochemical data. All concentrations from the Soil Re-Use Area and sediment samples are below Uniform radionuclide-specific derived concentration guideline level (DCGL{sub W}) limits; thus, comparisons to the less conservative stratified geometry were not required. Results were compared to individual DCGLs and using the sum of fractions approach. Both composite soil samples collected from the Waste Handling Area (Bins 1 and 4) were well below the prescribed USEI waste acceptance criteria.
Date: September 21, 2012
Creator: Bailey, Erika N. & Lee, Jason D.
Partner: UNT Libraries Government Documents Department

Enabling network-aware applications

Description: Many high performance distributed applications use only a small fraction of their available bandwidth. A common cause of this problem is not a flaw in the application design, but rather improperly tuned network settings. Proper tuning techniques, such as setting the correct TCP buffers and using parallel streams, are well known in the networking community, but outside the networking community they are infrequently applied. In this paper, we describe a service that makes the task of network tuning trivial for application developers and users. Widespread use of this service should virtually eliminate a common stumbling block for high performance distributed applications.
Date: August 1, 2001
Creator: Tierney, Brian L.; Gunter, Dan; Lee, Jason & Stouffer, Martin
Partner: UNT Libraries Government Documents Department

Improving the bulk data transfer experience

Description: Scientific computations and collaborations increasingly rely on the network to provide high-speed data transfer, dissemination of results, access to instruments, support for computational steering, etc. The Energy Sciences Network is establishing a science data network to provide user driven bandwidth allocation. In a shared network environment, some reservations may not be granted due to the lack of available bandwidth on any single path. In many cases, the available bandwidth across multiple paths would be sufficient to grant the reservation. In this paper we investigate how to utilize the available bandwidth across multiple paths in the case of bulk data transfer.
Date: May 7, 2008
Creator: Guok, Chin; Guok, Chin; Lee, Jason R. & Berket, Karlo
Partner: UNT Libraries Government Documents Department

Using High-Speed WANs and Network Data Caches to Enable Remote and Distributed Visualization

Description: Visapult is a prototype application and framework for remote visualization of large scientific datasets. We approach the technical challenges of tera-scale visualization with a unique architecture that employs high speed WANs and network data caches for data staging and transmission. This architecture allows for the use of available cache and compute resources at arbitrary locations on the network. High data throughput rates and network utilization are achieved by parallelizing I/O at each stage in the application, and by pipe-lining the visualization process. On the desktop, the graphics interactivity is effectively decoupled from the latency inherent in network applications. We present a detailed performance analysis of the application, and improvements resulting from field-test analysis conducted as part of the DOE Combustion Corridor project.
Date: April 18, 2000
Creator: Bethel, Wes; Lau, Stephen; Tierney, Brian; Lee, Jason & Gunter, Dan
Partner: UNT Libraries Government Documents Department

A monitoring sensor management system for grid environments

Description: Large distributed systems, such as computational grids,require a large amount of monitoring data be collected for a variety oftasks, such as fault detection, performance analysis, performance tuning,performance prediction and scheduling. Ensuring that all necessarymonitoring is turned on and that the data is being collected can be avery tedious and error-prone task. We have developed an agent-basedsystem to automate the execution of monitoring sensors and the collectionof event data.
Date: June 1, 2001
Creator: Tierney, Brian; Crowley, Brian; Gunter, Dan; Lee, Jason & Thompson, Mary
Partner: UNT Libraries Government Documents Department

Applied techniques for high bandwidth data transfers across wide area networks

Description: Large distributed systems such as Computational/Data Grids require large amounts of data to be co-located with the computing facilities for processing. Ensuring that the data is there in time for the computation in today's Internet is a massive problem. From our work developing a scalable distributed network cache, we have gained experience with techniques necessary to achieve high data throughput over high bandwidth Wide Area Networks (WAN). In this paper, we discuss several hardware and software design techniques and issues, and then describe their application to an implementation of an enhanced FTP protocol called GridFTP. We also describe results from two applications using these techniques, which were obtained at the Supercomputing 2000 conference.
Date: April 30, 2001
Creator: Lee, Jason; Gunter, Dan; Tierney, Brian; Allcock, Bill; Bester, Joe; Bresnahan, John et al.
Partner: UNT Libraries Government Documents Department

Network aware distributed applications

Description: Most distributed applications today manage to utilize only a small percentage of the needed and available network bandwidth. Often application developers are not aware of the potential bandwidth of the network, and therefore do not know what to expect. Even when application developers are aware of the specifications of the machines and network links, they have few resources that can help determine why the expected performance was not achieved. What is needed is a ubiquitous and easy-to-use service that provides reliable, accurate, secure, and timely estimates of dynamic network properties. This service will help advise applications on how to make use of the network's increasing bandwidth and capabilities for traffic shaping and engineering. When fully implemented, this service will make building currently unrealizable levels of network awareness into distributed applications a relatively mundane task. For example, a remote data visualization application could choose between sending a wireframe, a pre-rendered image, or a 3-D representation, based on forecasts of CPU availability and power, compression options, and available bandwidth. The same service will provide on-demand performance information so that applications can compare predicted with actual results, and allow detailed queries about the end-to-end path for application and network tuning and debugging.
Date: February 4, 2001
Creator: Agarwal, Deborah; Tierney, Brian L.; Gunter, Dan; Lee, Jason & Johnston, William
Partner: UNT Libraries Government Documents Department

A First Look at Modern Enterprise Traffic

Description: While wide-area Internet traffic has been heavily studied for many years, the characteristics of traffic inside Internet enterprises remain almost wholly unexplored. Nearly all of the studies of enterprise traffic available in the literature are well over a decade old and focus on individual LANs rather than whole sites. In this paper we present a broad overview of internal enterprise traffic recorded at a medium-sized site. The packet traces span more than 100 hours, over which activity from a total of several thousand internal hosts appears. This wealth of data--which we are publicly releasing in anonymized form--spans a wide range of dimensions. While we cannot form general conclusions using data from a single site, and clearly this sort of data merits additional in-depth study in a number of ways, in this work we endeavor to characterize a number of the most salient aspects of the traffic. Our goal is to provide a first sense of ways in which modern enterprise traffic is similar to wide-area Internet traffic, and ways in which it is quite different.
Date: June 1, 2005
Creator: Pang, Ruoming; Mark Allman, Mark; Bennett, Mike; Lee, Jason; Paxson, Vern & Tierney, Brian
Partner: UNT Libraries Government Documents Department

Essential Grid Workflow Monitoring Elements

Description: Troubleshooting Grid workflows is difficult. A typicalworkflow involves a large number of components networks, middleware,hosts, etc. that can fail. Even when monitoring data from all thesecomponents is accessible, it is hard to tell whether failures andanomalies in these components are related toa given workflow. For theGrid to be truly usable, much of this uncertainty must be elim- inated.We propose two new Grid monitoring elements, Grid workflow identifiersand consistent component lifecycle events, that will make Gridtroubleshooting easier, and thus make Grids more usable, by simplifyingthe correlation of Grid monitoring data with a particular Gridworkflow.
Date: July 1, 2005
Creator: Gunter, Daniel K.; Jackson, Keith R.; Konerding, David E.; Lee,Jason R. & Tierney, Brian L.
Partner: UNT Libraries Government Documents Department

The NIDS Cluster: Scalable, Stateful Network Intrusion Detection on Commodity Hardware

Description: In this work we present a NIDS cluster as a scalable solution for realizing high-performance, stateful network intrusion detection on commodity hardware. The design addresses three challenges: (i) distributing traffic evenly across an extensible set of analysis nodes in a fashion that minimizes the communication required for coordination, (ii) adapting the NIDS's operation to support coordinating its low-level analysis rather than just aggregating alerts; and (iii) validating that the cluster produces sound results. Prototypes of our NIDS cluster now operate at the Lawrence Berkeley National Laboratory and the University of California at Berkeley. In both environments the clusters greatly enhance the power of the network security monitoring.
Date: September 19, 2007
Creator: Tierney, Brian L; Vallentin, Matthias; Sommer, Robin; Lee, Jason; Leres, Craig; Paxson, Vern et al.
Partner: UNT Libraries Government Documents Department

Interactive Analysis of Large Network Data Collections UsingQuery-Driven Visualization

Description: Realizing operational analytics solutions where large and complex data must be analyzed in a time-critical fashion entails integrating many different types of technology. Considering the extreme scale of contemporary datasets, one significant challenge is to reduce the duty cycle in the analytics discourse process. This paper focuses on an interdisciplinary combination of scientific data management and visualization/analysis technologies targeted at reducing the duty cyclein hypothesis testing and knowledge discovery. We present an application of such a combination in the problem domain of network traffic data analysis. Our performance experiment results, including both serial and parallel scalability tests, show that the combination can dramatically decrease the analytics duty cycle for this particular application. The combination is effectively applied to the analysis of network traffic data to detect slow and distributed scans, which is a difficult-to-detect form of cyber attack. Our approach is sufficiently general to be applied to a diverse set of data understanding problems as well as used in conjunction with a diverse set of analysis and visualization tools.
Date: December 1, 2005
Creator: Bethel, E. Wes; Campbell, Scott; Dart, Eli; Lee, Jason; Smith,Steven A.; Stockinger, Kurt et al.
Partner: UNT Libraries Government Documents Department