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Gunter, Dan

Publications and source records attributed to Gunter, Dan.

40 records · Page 3
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NASA NTRS2001

Simple LDAP Schemas for Grid Monitoring

The purpose of this document is to provide an initial definition of the data we need in a directory service or database so that we can implement a performance monitoring testbed. To begin with, this document describes how to represent producers of events and event schemes. The representation of producers is simple and does not contain information such as who has access to the events and what protocols can be used to access the events. In the future, we will define how to describe consumers of events and add details to our representations. A popular choice for a directory service or database for grid computing is a distributed directory service that is accessed using the Lightweight Directory Access Protocol (LDAP). This document uses LDAP terminology, schemes, and formats to represent the directory service schemes.

Smith, Warren↗
NASA NTRS2001

A Simple XML Producer-Consumer Protocol

There are many different projects from government, academia, and industry that provide services for delivering events in distributed environments. The problem with these event services is that they are not general enough to support all uses and they speak different protocols so that they cannot interoperate. We require such interoperability when we, for example, wish to analyze the performance of an application in a distributed environment. Such an analysis might require performance information from the application, computer systems, networks, and scientific instruments. In this work we propose and evaluate a standard XML-based protocol for the transmission of events in distributed systems. One recent trend in government and academic research is the development and deployment of computational grids. Computational grids are large-scale distributed systems that typically consist of high-performance compute, storage, and networking resources. Examples of such computational grids are the DOE Science Grid, the NASA Information Power Grid (IPG), and the NSF Partnerships for Advanced Computing Infrastructure (PACIs). The major effort to deploy these grids is in the area of developing the software services to allow users to execute applications on these large and diverse sets of resources. These services include security, execution of remote applications, managing remote data, access to information about resources and services, and so on. There are several toolkits for providing these services such as Globus, Legion, and Condor. As part of these efforts to develop computational grids, the Global Grid Forum is working to standardize the protocols and APIs used by various grid services. This standardization will allow interoperability between the client and server software of the toolkits that are providing the grid services. The goal of the Performance Working Group of the Grid Forum is to standardize protocols and representations related to the storage and distribution of performance data. These standard protocols and representations must support tasks such as profiling parallel applications, monitoring the status of computers and networks, and monitoring the performance of services provided by a computational grid. This paper describes a proposed protocol and data representation for the exchange of events in a distributed system. The protocol exchanges messages formatted in XML and it can be layered atop any low-level communication protocol such as TCP or UDP Further, we describe Java and C++ implementations of this protocol and discuss their performance. The next section will provide some further background information. Section 3 describes the main communication patterns of our protocol. Section 4 describes how we represent events and related information using XML. Section 5 describes our protocol and Section 6 discusses the performance of two implementations of the protocol. Finally, an appendix provides the XML Schema definition of our protocol and event information.

Smith, Warren↗
NASA NTRS2001

An XML-Based Protocol for Distributed Event Services

This viewgraph presentation provides information on the application of an XML (extensible mark-up language)-based protocol to the developing field of distributed processing by way of a computational grid which resembles an electric power grid. XML tags would be used to transmit events between the participants of a transaction, namely, the consumer and the producer of the grid scheme.

Smith, Warren↗
NASA NTRS2000

A Simple XML Producer-Consumer Protocol

This document describes a simple XML-based protocol that can be used for producers of events to communicate with consumers of events. The protocol described here is not meant to be the most efficient protocol, the most logical protocol, or the best protocol in any way. This protocol was defined quickly and it's intent is to give us a reasonable protocol that we can implement relatively easily and then use to gain experience in distributed event services. This experience will help us evaluate proposals for event representations, XML-based encoding of information, and communication protocols. The next section of this document describes how we represent events in this protocol and then defines the two events that we choose to use for our initial experiments. These definitions are made by example so that they are informal and easy to understand. The following section then proceeds to define the producer-consumer protocol we have agreed upon for our initial experiments.

Smith, Warren↗