Host-Network Interface Architecture for Gigabit Communications

There are two complementary trends in the computer and communications fields. Increasing processor power and memory availability allow more demanding applications, such as scientific visualizations and imaging. Advances in network performance and functionality have the potential for supporting applications requiring high bandwidth communications. However, the bottleneck is increasingly in the host-network interface, and thus the ability to deliver high performance communications capability to applications has not kept up with the advance in computer and network speed. We have proposed a new architecture that meets these challenges, called Axon. The Axon thesis is that an essential requirement for the support of high performance distributed IPC is to provide a direct channel for object transfer between the communicating processes. Thus, this research centers on how to create an end-to-end pipeline to deliver this high bandwidth to applications. The goals are to develop a suitable architecture, determine the key issues and tradeoffs, and evaluate them as data rates scale beyond 1 Gbps. Novel aspects of this research include: an integrated design of hardware, operating systems, and communications protocols, stressing both performance and the required functionality for demanding applications; the proper division of hardware and software function; and reorganization of end-to-end protocols to take advantage of the increased functionality of the emerging high speed internetworks

Hardware Based Error and Flow Control in the Axon Gigabit Host-Network Interface

We have proposed a new architecture called Axon that meets the challenges of delivering high performance network bandwidth directly to applications. Its pipelines network interface must perform critical per packet processing in hardware a packets flow through the pipeline, without imposing any store-and-forward buffering of packets. This requires the design of error and flow control mechanisms to be simple enough for implementation in the network interface hardware, while providing functionality required by applications. This paper describes the implementation of the Axon host-network interface, and in particular the hardware design of the critical per packet processing with emphasis on error and flow control. An extensive simulation model of the network interface hardware has been used to determine the feasibility and performance of hardware implementation of these functions

Disciplines and measures of information resilience

Communication networks have become a fundamental part of many critical infrastructures, playing an important role in information delivery in various failure scenarios triggered e.g., by forces of nature (including earthquakes, tornados, fires, etc.), technology-related disasters (for instance due to power blackout), or malicious human activities. A number of recovery schemes have been defined in the context of network resilience (with the primary focus on communication possibility in failure scenarios including access to a particular host, or information exchange between a certain pair of end nodes). However, because end-users are becoming more and more interested in information itself (regardless of its physical location in the network), it is appropriate to complement the well-defined framework of network resilience with one that addresses information resilience, and to introduce definitions of relevant disciplines and measures, as proposed in this paper

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Determining crystal structures through crowdsourcing and coursework

We show here that computer game players can build high-quality crystal structures. Introduction of a new feature into the computer game Foldit allows players to build and real-space refine structures into electron density maps. To assess the usefulness of this feature, we held a crystallographic model-building competition between trained crystallographers, undergraduate students, Foldit players and automatic model-building algorithms. After removal of disordered residues, a team of Foldit players achieved the most accurate structure. Analysing the target protein of the competition, YPL067C, uncovered a new family of histidine triad proteins apparently involved in the prevention of amyloid toxicity. From this study, we conclude that crystallographers can utilize crowdsourcing to interpret electron density information and to produce structure solutions of the highest quality