This issue of XML Daily Newslink is sponsored by:
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- An Analysis of XML Compression Efficiency
- W3C Candidate Recommendation: SPARQL Query Results XML Format
- Federated Access Manager 8.0: Features
- Microsoft Passes AJAX Interoperability Test
- Information Model and XML Data Model for Traceroute Measurements
- Government Policy and "Standards Based Neo-Colonialism"
- Brazil's Minister of Culture Calls for Free Digital Society
An Analysis of XML Compression Efficiency
Chris Augeri, Barry Mullins (et al.), Conference Paper
This paper was presented at the 2007 Workshop on Experimental Computer Science (ExpCS '07) in San Diego, CA, 13-14 June 2007 (12 pages, with 51 references). XML has gained much acceptance since first proposed in 1998 by the World Wide Web Consortium (W3C). The XML format uses schemas to standardize data exchange amongst various computing systems. However, XML is notoriously verbose and consumes significant storage space in these systems. To address these issues, the W3C formed the Efficient XML Interchange Working Group (EXI WG) to specify an XML binary format. Although a binary format foregoes interoperability, applications such as wireless devices use them due to system limitations. Binary formats encode XML documents as binary data. The intent is to decrease the file size and reduce the required processing at remote nodes. If XML binary formats are to succeed, an open standard must be established. The primary impetus for binary XML is the limited capabilities of wireless devices, e.g., cell phones and sensor networks. Further pressure to use a binary format comes from the growth of large repositories, e.g., databases that store data using an XML format. Technically, both compressed and binary formats are 'binary' formats, versus plaintext, but binary formats may support random access and queries, whereas compression formats often do not. Statistical methods are often used for analyzing experimental data; however, computer science experiments often only provide a comparison of means. We describe how we used more robust statistical methods, i.e., linear regression, to analyze the performance of 14 compressors against a corpus of XML files we assembled with respect to an efficiency metric proposed herein. Our end application is minimizing transmission time of an XML file between wireless devices, e.g., nodes in a distributed sensor network (DSN), for example, an unmanned aerial vehicle (UAV) swarm. Thus, we focus on compressed file sizes and execution times, foregoing the assessment of decompression time or whether a particular compressor supports XML queries... We present an XML test corpus and a combined efficiency metric integrating compression ratio and execution speed. We also identify key factors when selecting a compressor. Our results show XMill or WBXML may be useful in some instances, but a general-purpose compressor is often the best choice. Additional information about the study, including links to the XML corpus used in the paper, is available as supporting data from Chris Augeri.
See also: the supporting data
W3C Candidate Recommendation: SPARQL Query Results XML Format
Dave Beckett and Jeen Broekstra (eds), W3C Technical Report
Members of the W3C RDF Data Access Working Group have announced the advancement of the "SPARQL Query Results XML Format" specification to Candidate Recommendation. W3C publishes a Candidate Recommendation to gather implementation experience. The RDF Data Access Working Group has already gathered implementation experience for this specification as part of developing the "SPARQL Query" and "SPARQL Protocol" specifications. Rather than request to advance directly to Proposed Recommendation, the group has requested to use this Candidate Recommendation period to identify additional implementations, such as automated consumers of SPARQL XML Results, and to provide implementers of SPARQL Query and SPARQL Protocol with a suitably stable specification. The design has stabilized and the Working Group intends to advance this specification to Proposed Recommendation once the exit criteria are met, viz., when the SPARQL Query Results XML Format has at least two implementations. The specification will remain a Candidate Recommendation until at least 9-October-2007, and an implementation report will be produced. The specification describes an XML format for the variable binding and boolean results formats provided by the SPARQL query language for RDF as part of the Semantic Web Activity. RDF is a flexible, extensible way to represent information about World Wide Web resources. It is used to represent, among other things, personal information, social networks, metadata about digital artifacts like music and images, as well as provide a means of integration over disparate sources of information. A standardized query language for RDF data with multiple implementations offers developers and end users a way to write and to consume the results of queries across this wide range of information. With the propoed format, SPARQL variable binding and boolean results can be expressed in XML.
See also: W3C RDF Data Access Working Group
Federated Access Manager 8.0: Features
Daniel Raskin, Blog
This article is part 2 of a presentation on a [Sun] Federated Access Manager (FAM) product. "We're in the process of combining Access Manager and Federation Manager in to a single product called Federated Access Manager (FAM). Scheduled to release in March 2008, the product will be built from a single, externally managed and accessible code base, which is part of an open source project called OpenSSO. All builds of FAM are publicly available via the OpenSSO web site. FAM will be delivered as a self-contained J2EE application. Delivering the product as a pure J2EE application provides ease of deployment and minimizes the number of processes that are running at one time. This enables Sun to provide access management, federation, and web services security functionality out of the box and delivered as a simple WAR file that can be deployed in minutes. Other Federation/WAM solutions often require the deployment of multiple components, scripts and have multiple processes running at once. Features: (1) Simplified Platform: The FAM 8.0 release will focus on significantly simplifying functionality for the user so that they can easily complete the most commonly used tasks during pre- and post-configuration in a jiffy. These simplified workflows will be dynamic and allow the customer to very quickly deploy a completely load balanced solution in minutes. (2) Heterogeneity: We will continue to support a diverse range of protocols, containers, directories, WAM, Federation and OS platforms so that customers can choose what best fits their needs. In addition to supporting Active Directory and Sun Java System Directory Server, we will be expanding our directory support to include Tivoli Directory Server. (3) Access Management Features: The FAM 8.0 product release will focus on improving the ease of deployment of the Access Management solution by centralizing agent configuration and AM instance configuration. We will also be expanding our protocol support to include XACML support. The major access management features in the 8.0 release are centralized Agent Configuration and Deployment, Centralized Instance Configuration, and XACML Request/Response. (4) Federation Management: The focus on federation will be expanding our product interoperability so that customers can implement our federation service without having to change their internal architecture or infrastructure... [including support for] WS-Federation 1.1, Simple Federated Partner Enablement, Multi-Federation Protocol Hub, and Secure Attribute Exchange to federate-enable legacy applications. (5) Identity Services, supporting Authentication as a service, Authorization as a service, Audit as a service, Attribute Query as a service, and Generalized Trust Authority—STS that supports Liberty and WS-Trust based interactions. (6) Web Services Security: We are expanding our web service security story so that customers can implement plug-ins to protect web services rather than doing it programmatically... [plugins and containers] Sun Java System Application Server, Sun Java System Web Server, BEA Weblogic, and IBM Websphere.
See also: FAM 8.0 Part 1
Microsoft Passes AJAX Interoperability Test
Stuart J. Johnston, InternetNews.com
Microsoft quietly announced in a pair of blog posts this week that it has passed the OpenAJAX InteropFest 1.0 interoperability tests, meaning that its AJAX tools work in an OpenAJAX environment. The Redmond, Wash. software company just joined the year-and-a-half-old OpenAJAX Alliance in March. AJAX has become a mainstay for programming applications on the Web. The acknowledgment that Microsoft's AJAX toolset had passed came from a blog post by Brad Abrams, group program manager at Microsoft for ASP.NET AJAX, formerly codenamed Atlas. ASP.NET AJAX was developed to simplify writing AJAX applications using Microsoft's .Net technologies. Microsoft shipped version 1 of the ASP.NET AJAX extensions and controls in January. An alliance statement this week confirmed Microsoft's tools passed the interoperability tests. The alliance was initially formed in early 2006 by IBM, along with Google, Yahoo, BEA, Borland, the Eclipse Foundation, Mozilla Corporation, Novell, Oracle, Red Hat, and others. Now its membership is up to 90 companies, organizations, and interested parties, and includes other heavy hitters such as Cisco, Sun Microsystems, Fidelity Investments and American Greetings.
See also: the OpenAjax Alliance
Information Model and XML Data Model for Traceroute Measurements
S. Niccolini, S. Tartarelli, J. Quittek, M. Swany (eds), IETF I-D
IETF announced the availability of a new draft in the online Internet Drafts directories. "Information Model and XML Data Model for Traceroute Measurements" is a work item produced by members of the IP Performance Metrics Working Group of the IETF. The IETF IPPM Working Group Working Group was chartered to develop a set of standard metrics that can be applied to the quality, performance, and reliability of Internet data delivery services. These metrics are designed such that they can be performed by network operators, end users, or independent testing groups. Traceroute is a network diagnostic tool used to determine the hop by hop path from a source to a destination and the Round Trip Time (RTT) from the source to each hop. Traceroute can be therefore used to discover some information (hop counts, delays, etc.) about the path between the initiator of the traceroute measurement and other hosts. Typically, the traceroute tool attempts to discover the path to a destination by sending UDP probes with specific time-to-live (TTL) values in the IP packet header and trying to elicit an ICMP TIME_EXCEEDED response from each gateway along the path to some host. Traceroutes are being used by lots of measurement efforts, either as an independent measurement or to get path information to support other measurement efforts. That is why there is the need to standardize the way the configuration and the results of traceroute measurements are stored. The standard metrics defined by IPPM working group in matter of delay, connectivity and losses do not apply to the metrics returned by the traceroute tool; therefore, in order to compare results of traceroute measurements, the only possibility is to add to the stored results a specification of the operating system and version for the traceroute tool used. This document, in order to store results of traceroute measurements and allow comparison of them, defines a standard way to store them using a XML schema. Section 7 contains the XML schema to be used as a template for storing and/or exchanging traceroute measurements information. The schema was designed in order to use an extensible approach based on templates (similar to how IPFIX protocol is designed) where the traceroute configuration elements (both the requested parameters, Request, and the actual parameters used, MeasurementMetadata) are metadata to be referenced by results information elements (data) by means of the TestName element (used as unique identifier). Currently Open Grid Forum (OGF) is also using this approach and cross- requirements have been analyzed. The XML schema is compatible with OGF schema since it was designed in a way that both limits the unnecessary redundancy and a simple one-to-one transformation between the two exist.
Government Policy and "Standards Based Neo-Colonialism"
Andrew Updegrove, Blog
"From the sixteenth through the nineteenth centuries, European powers colonized most of the rest of the world in order to exploit the natural resources, inexpensive labor, and new markets that became available in the wake of the great voyages of discovery. These comparatively more developed nations were able to do so in part as a result of their superior technology and capital resources. Today, the developed world and its institutions are sometimes criticized for "neocolonial" activities that allow them still to exploit, or unduly influence, their former colonies. One manner in which multinational corporations can engage in similar conduct is through their control of the patents that underlie many important standards. When such standards bear royalties, the patent owners can relegate emerging nations to low-cost job shops that are able to build products, on order and at low profit margins, for foreign brands, but not to sell similar products under their own brands at higher profit margins. The predictable result is the development by nations (most notably China) of duplicative "home grown" standards. Unless greater efforts are made to avoid royalties and other restrictive terms in standards-related patent licenses, it is therefore likely that increasing numbers of standards wars will break out in the future, obstructing international trade. In this article, I explore the roots of this phenomenon, and suggest ways in which the situation might be redressed."
Brazil's Minister of Culture Calls for Free Digital Society
Martin LaMonica, CNET News.com
Free culture advocate and Brazilian Minister Gilberto Gil said at the MIT at Emerging Technology conference that digital technology offers a rare opportunity to bring knowledge to under-privileged people around the world and to include them in the political process. He called for loosening intellectual property regulations to give more people the freedom to use and republish digital forms of content as a way of encouraging personal expression, culture and political participation. As Minister of Culture, Gil helped spearhead the creation of 650 "cultural hot spots" where people have access to free software and computers, typically for the first time. During his speech, Gil called on other countries to adopt more liberal policies in regard to intellectual property, patents and copyright. Within Brazil, his ministry is trying to reform copyright laws that contain several holes that don't address issues such as personal use. At an international level, Brazil has, through a United Nations forum, called for international regulations that tilt the balance of control over content away from publishers and toward consumers, particularly in developing countries. The public domain should be a "necessary dimension of the intellectual property system," he said. This same philosophy applies to realm of software. "Of course we are going to face problems of guaranteeing property and renumeration of property on one side and the public interest on the other side. What's needed is more discussion of the proper balance in the political realm. Since being Minister of Culture, he has worked with the Creative Commons group to allow musicians to permit others to take their creations and use them in various forms.
See also: Creative Commons references
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