Building Peer-to-Peer XML Content Networks of Web Services for Federal\
Scientific and Statistical Data and Information: FedStats.Net and Beyond

*By Brand L. Niemann*

*Environmental Protection Agency (EPA)*

 

**Summary**

XML is a new standard for preserving and communicating
information---encoding, tagging, and internationalizing on the World
Wide Web. Web services use XML data and messages to provide
communication between applications running on different Web servers that
will bring the Internet to its new level (called the third generation).
Peer-to-Peer (P2P) architectures are best understood by thinking in
terms of Presence, Identity, and Edge (PIE) resources that offer
powerful approaches for solving the seemingly intractable problems of
the Web and for creating a more efficient and robust Internet. P2P
creates the most significant challenges to traditional centralized IT
departments and security models. XML data and meta data architectures
are connected because (1) from a "resource perspective," meta data is
either external to or embedded within the data, while (2) from a "client
perspective," metadata is either centralized or distributed.
Peer-to-peer approaches are needed in a more distributed environment to
simultaneously query, discover, and aggregate the data and meta data
results locally.

 

Peer-to-Peer XML Web services is the technology underlying new programs
like the EPA National Environmental Exchange Network and Central Data
Exchange, content networks, and several E-GOV initiatives. Everyone in
the Federal government should know something about Peer-to-Peer XML Web
services.

**Contents**

1.  Introduction

2.  Virtual Centralization of Diverse and Distributed Content

3.  Environmental Node on a FedGov Content Network

4.  Permanent Public Access Archive

5.  Pilot FedGov Content Network

6.  Value Proposition for the Federal Government

7.  XML Web Services Training

8.  Acknowledgements

9.  References

 

**1. Introduction**

The EPA goal is to create a National Environmental Information Exchange
Network (see figure 1 below), an Internet-based system where
standardized environmental data is rationally shared and easily
accessible. With EPA and each state having one point of entry, or node,
and following agreed-upon formats, EPA and the states see many benefits.
These include reduced data redundancy, better-quality data, improved
security, and, ultimately, better environmental policy \[1\].

 

![](media/image1.png){width="3.3715277777777777in"
height="2.5305555555555554in"}

**Figure 1 - Schematic of National Environmental Information\
Exchange Network Vision**

 

The National Environmental Exchange Network has been cited recently as
an excellent example of "Achieving the Vision of E-Government" \[2\],
because from a technology perspective, Messaging and Web Services have
become the key enabler to convergence.

1.  Global trade requires global communications and increasingly involve
    e-markets, e-procurement, online product development, supply
    chains/value Webs;

2.  Trade requires data exchange and information processing capabilities
    from data storage, to transaction processing, to standard protocols;
    and

3.  Legacy and new systems are coded in multiple languages (COBOL still
    dominant, C++, Java, Ada, etc.), and were modernized by Y2K
    remediation. 

So, XML.ORG and the World Wide Web Consortium (W3C) have embraced
messaging standards (SOAP) and "services" (UDDI) to allow communications
between standard platforms and a broad range of legacy applications.

 

This means that users must have a unified view of data and simple
business processes in order to reap benefits from Emerging Web Services
Technologies. Further, e-government opportunities create benefits
throughout the Information Value Chain: Capture, Store, Query,
Distribute, Analyze, Act, and Learn \[2\]. Specifically, these new
technologies and opportunities:

1.  Reduce burden---for example, applying online for services,
    submitting data and payments on-line;

2.  Reuse information, consolidate databases, and unify islands of
    automation to reduce maintenance and usage costs---e.g. peer-to-peer
    or search vs. data warehouses;

3.  Publish information to devolve governance to local communities; and

4.  Improve knowledge management to improve decisions, yielding better
    service, faster and at lower costs.

>  

This paper reports on some pilot efforts to build Peer-to-Peer XML
Content Networks of Web Services for Federal Scientific and Statistical
Data and Information. It begins with an effort called "An Integrated
Repository and Registry for Environmental Information" \[4\], then
FedStats.Net \[5-9\], an outgrowth of the FedStats.Gov activity
\[10-16\] and more recently called the Pilot FedGov Content Network
\[17-23\].

# 2. Virtual Centralization of Diverse and Distributed Content

A recent Gartner Group Report \[24\] describes the emergence of
distributed content management and Peer-to-Peer Content Networks. The
Integrated Repository and Registry for Environmental Information \[4\]
and FedStats.Net 5-9\] used NXT 3 P2P Platform from NextPage to pilot
the use of messaging between Web servers and Web services that integrate
information and applications for environmental and Federal statistical
data and information. The NXT 3 interface (see Figure 2 below) combines
contents networks (left pane), portals and "portlets" (center pane), and
services like search, personalization, document management, and metadata
(top banner). In a business application, the "portlets" are usually
e-mail, stock, and news feeds. In our environmental and statistical
applications, the "portlets" are passing the XML data to mapping and
statistical analyses applications. The content network system of
hierarchical folders (left pane) can be likened to the Windows Explorer
tool where diverse file types can be organized into folders. However,
with NXT 3, the diverse file types and folders can and should be on
different Web servers where the content originates and is maintained.

![](media/image2.png){width="3.747916666666667in"
height="2.152083333333333in"}\
**Figure 2 - Schematic Diagram of the NXT 3 P2P Platform Interface**

** **

**3. Environmental Node on a FedGov Content Network**

The Integrated Repository and Registry for Environmental Information
\[4\] (see Figure 3 below) has grown to become the Environmental Node on
the FedGov Content Network. This includes the FedStats.Net \[5-9\]
content, plus other content added more recently to demonstrate the
versatility of the NXT 3 P2P Platform. The environmental information is
organized by what users want to know, namely, what is the state of the
environment, how good is the data the state of the environment is based
on (called metadata for data about data), what are the databases used in
the assessing the state of the environment, and what is the best
information about the environment organized by themes.

![](media/image3.jpeg){width="3.4972222222222222in"
height="2.285416666666667in"}

**Figure 3 - Screen Capture of the NXT 3 P2P Platform Interface for the\
Environmental Node on the FedGov Content Network\
**

**4. Permanent Public Access Archive**

The NXT 3 P2P Platform has also been used to pilot (1) the archiving of
distributed and diverse content to provide "permanent public access" and
(2) the creation of new content nodes with added-value through the use
of XML and Web services. This has been done with selected environmental
and Federal statistical and scientific content like the Environmental
Statistics (see Figure below), which archives about 200 HTML and Excel
files that are updated periodically. Section 102 of the National
Environmental Policy Act (NEPA) requires the Federal government to
gather significant environmental data prior to decision-making and to
make information useful in restoring, maintaining, and enhancing the
quality of the environment available to states, counties,
municipalities, institutions, and individuals. Critical to sound
environmental decision-making under NEPA is having environmental data
available for analysis. This Environmental Statistics site contains the
longest running set of consistent environmental data. It contains
updated information and provides access to statistical tables and
references that formerly appeared in "Part III -Environmental Data and
Trends" of the Annual Reports for the Council on Environmental Quality.

 

![](media/image4.jpeg){width="3.4659722222222222in"
height="2.5083333333333333in"}

**Figure 4 - Screen Capture of the NXT 3 P2P Platform Interface for the
Environmental Statistics\
Node Archive on the FedGov Content Network\
**

** **

![](media/image5.jpeg){width="3.688888888888889in"
height="2.7472222222222222in"}

**Figure 5 - Screen Capture of the NXT 3 P2P Platform Interface for the
FedGov Content Network Portal\
**

**5. Pilot FedGov Content Network**

The pilot FedGov content network was assembled by using the NXT 3 P2P
platform to link multiple Web servers with distributed content. The
purpose was to test the messaging functionality of making distributed
content look and function as though it was all on one Web server, when
in actuality it was on multiple Web servers (see Figure above). At one
point in the pilot work, we had diverse content on up to six Web
servers, including the extremes of Web servers in California and
Washington, D.C., and servers next to one another.

 

**6. Value Proposition for the Federal Government**

1.  The value proposition is:XML "future proofs" information against
    periodic technology change, facilitates integration, and promotes
    collaboration;

2.  P2P reduces costs of integration and can replace data replication
    and warehousing; and

3.  Web services provide communication between applications running on
    different Web servers that will bring the Internet to its new level.

>  

The NXT 3 P2P Platform has provided excellent support for our
XML/P2P/Web Services pilot projects.

 

**7. XML Web Services Training**

A system of XML Web Services training has been developed for both
managers and specialists to support the EPA Central Data Exchange and
Region and State Network Node building process. The multiple levels are
briefly described below:

1.  XML Web Services: Introduction

2.  Introduction to XML Video

3.  Introduction to XML for the Web: Step-by-Step

4.  Basic Training in the EPA Network Node Pilot Projects: Alpha and
    Beta Phase

5.  XML Web Services: XML Asset Management Using XML Spy 4.2 and TIBCO
    Canon/Developer Portal

6.  XML Web Services: Technologies and Security Models

7.  XML Web Services: XML-ization of Databases and Metadata

8.  XML Web Services: Building at the National, Regional, and State
    levels

9.  XML Web Services: Standard by Standard

10. XML Web Services: Best Practices

11. XML Web Services: Overview of Microsoft.Net

12. XML Web Services: The Semantic Web and Ontologies

Disclaimer: Any reference to or depiction of the commercial product of
any vendor is for illustrative purposes only and does not constitute an
endorsement by EPA or the trainer.

**8. Acknowledgments**\
The author acknowledges the contributions to this work of his many
FedStats.Gov and FedStats.Net colleagues over the years, and his
association with XML.GOV (Owen Ambur and Marion Royal, co-leaders),
CENDI, Federal Content Managers Group, EPA Web Working Group, GPO
Federal Institute for Printing and Electronic Publishing (Carol Cini,
Director), and EPA National Exchange Network and Central Data Exchange
and workers.

>  

**9. References**

1.  A Networked Environment, Federal Computer Week, Greg Langlois, June
    18, 2001,
    <http://www.fcw.com/fcw/articles/2001/0618/pol-epa-06-18-01.asp>

2.  Achieving the Vision of E-Government, Mark Forman, Associate
    Director for IT and E-Government, OMB, October 2001, 18 slides.

3.  The XML Files and XML Project Centralizes Agency Statistics, Federal
    Computer Week Article, January 8, 2001,
    <http://www.fcw.com/fcw/articles/2001/0108/cov-xmlbx3-01-08-01.asp>

4.  Niemann, B. 2000: An Integrated Repository and Registry for
    Environmental Information: An XML Portal for Public Access and Data
    Exchange, Discussion paper for INFOTERRA 2000-Global Conference on
    Access to Environmental Information, Dublin, Ireland, 11-15
    September.
    <http://www.unep.org/infoterra/infoterra2000/Brand-rev.doc>

5.  Niemann, B.L., FedStats.Net, November 2000, Federal Conference on
    Statistical Methodology,

6.  Niemann, B.L., et al, FedWeb 2001 Conference, Portals: How
    E-Government Is Transforming Communications With Citizens: From
    Portals to Peer Space, and The Future of Portals: Case Study of
    FedStats as a Model for Collaboration and Data Integration, March
    2001,
    [http://www.fedweb.org/FedWeb2001Presentations/Future%2520of%2520Portals-FedStats%5b1%5d.ppt](http://www.fedweb.org/FedWeb2001Presentations/Future%2520of%2520Portals-FedStats%5B1%5D.ppt)
    and
    [http://www.fedweb.org/FedWeb2001Presentations/Portals%2520to%2520Peer-to-Peer%5b1%5d.ppt](http://www.fedweb.org/FedWeb2001Presentations/Portals%2520to%2520Peer-to-Peer%5B1%5D.ppt).

7.  Peer-to-Peer Isn\'t Dead\", The Industry Standard Magazine, April
    23, 2001

8.  NextPage Bridges Islands of Content\", ComputerWorld, May 28, 2001,
    <http://www.computerworld.com/cwi/story/0,1199,NAV47-71-365-383_STO60858,00.html>

9.  \"All in a day\'s work\" and \"Computers with a view\", Federal
    Computer Week,
    <http://fcw.com/fcw/articles/2001/0514/mgt-profile-05-14-01.asp>
    and,
    <http://fcw.com/fcw/articles/2001/0514/cov-fednap-05-14-01.asp>.

10. Capps, C., Green, A. and Wallace, M., 1999: The Vision of Integrated
    Access to Statistics: the Data Web, Of Significance, Volume 1,
    Number 2, 42-47, Association of Public Data Users.

11. DeBerry, M., Gregg, V., and Taylor, R. FedStats: Creating the U.S.
    National Statistical Information Infrastructure of the 21^st^
    Century, UN/ECE Seminar on Integrated Statistical Information
    Systems (ISIS), Riga, Latvia, 29-31 May 2000.

12. Marchionini, G. and Hert, C., 2000: Interacting with Tabular Data
    Through the WWW, in proceeding of this conference
    (<http://istweb.syr.edu/~tables/>).

13. Wallace, M. and Cortez, J.A., 2000: Developing and Promoting
    Next-Generation Inormation Products for
    [WWW.CENSUS.GOV](http://www.census.gov/) and
    [WWW.FEDSTATS.GOV](http://www.fedstats.gov/), Census Advisory
    Committee of Professional Associations, October 19-20, 12 pp.

14. Wallace, M. and Highsmith, S. 1999: Use of Metadata for the
    Effective Integration of Data from Multiple Sources, ICES paper,
    8pp.

15. Wallace, M., and Sperling, J. User-Driven Integrated Statistical
    Solutions (Version 08/28/00), accepted for publication in URISA
    Journal,
    http://www.urisa.org/Journal/accepted/sperling/user_drivewn_integrated_statistical_solutions.htm

16. Wallman, K.K., Zawitz, M.W., Blessing, C., and Treadwell, W., 1999:
    Making Things Add Up For the End Uses: Issues in Statistical
    Literacy, Of Significance, Volume 1, Number 2, 14-16, Association of
    Public Data Users.

17. Niemann, B.L., XML/P2P/Web Services in EPA, XML.GOV, & E-GOV,
    O\'Reilly Peer-to-Peer and Web Services Conference, November 5-8,
    2001, 10 slides.

18. Niemann, B.L., Building P2P/XML Content Networks of Web Services for
    Federal Scientific and Statistical Data and Information:
    FedStats.Net and Beyond, 2001 S-PLUS International User Conference,
    October 18-19, 2001, 41 slides.

19. Niemann, B.L., 2001 Federal Depository Library Conference, Agency
    Update: USEPA, October 15, 2001, 33 slides.

20. Niemann, B.L., Maximizing Peer-to-Peer Portal Through XML: An
    Integration Case Study from EPA, Enterprise Web and Corporate Portal
    Conference, September 5-6, 2001, 49 slides.

21. Niemann, B.L., What is XML?:A practical introduction for EPA
    Webmasters, EPA Web Working Group Meeting, July 24-26, 2001, 40
    slides.

22. Niemann, B.L., XML@EPA, EPA National Developers Conference, April
    3-5, and Veterans Administrations, April 10, 2001, 31 slides.

23. Niemann, B.L., XML for Information and Application Integration,
    Federal CIO XML Working Group Presentation,
    <http://xml.gov/agenda/20010117.htm>.

24. The Emergence of Distributed Content Management and Peer-to-Peer
    Content Networks,
    <http://www.nextpage.com/pdfs/wp_Gartner_final.pdf>

For more information, contact Brand L. Niemann, Ph.D by telephone at
(202) 260-2510 or via e-mail at <niemann.brand@epa.gov>,
[http://fedgov.nextpage.com](http://198.60.24.137/NXT/gateway.dll?f=templates&fn=default.htm&vid=us census:enu)
or <http://www.sdi.gov/server.htm>.