DE 2.0 latest updates

["Jeff Waters" <jeff.waters@navy.mil>]

Hello all:

  The latest version of the DE 2.0 zip has been uploaded. Only minor changes to import statements were made to include the latest version of the extensions schema which Brian sent in email earlier in the month and which was reviewed and approved by EM TC. Our next step is to approve proceeding with the DE 2.0 to include the extensions.  The extensions concept and overview are included in the DE Basics white paper which is in the zip or available for separate download in the IF documents.  A brief summary of extensions is provided below.  Thanks.

--Jeff

DE 2.0 Extensions Overview

The DE 2.0 now supports the inclusion of community-defined sets of name/value pairs, referred to here as “Community Extensions” or simply “Extensions” for short.  Users of the Common Alert Protocol (CAP) are familiar with this concept since CAP was the first EDXL standard to include the Parameter element which allows a user to add name/value data to a normal CAP alert.  The Canadian Emergency Management community has been utilizing the Parameter elements to send supplemental business information, referred to as “layers”, with CAP for years.  Now, you can do the same with the DE and other EDXL standards.  For example, if you send a DE message with an alert or image about an earthquake, you might want to include some specific earthquake data, like the magnitude and depth of the earthquake. There are no earthquake-specific fields in the DE; however, your community can extend the DE to include that information, which you define as a set of Parameter elements specifically, designed to represent earthquake data. Although standards’ developers sometimes frown upon such extension mechanisms, since they appear to allow for arbitrary, non-standard representation of information, the “Community Extensions” concept solves several major problems for improving information sharing and developing standards for the emergency management community. First, the nature of emergencies is that the unexpected will happen and emergency managers need flexibility  to send whatever information is needed .  Second, an emergency begins and often stays local, so local authorities and users need control to send the information they decide is important to address the current emergency. Third, communities need the opportunity to explore potential new standards. The Parameter name/value extension mechanism, along with the concept and formalism of “Community Extensions”, provides an on-ramp for communities to determine what works well for them. Those Community Extensions which are most successful can be formalized into future standards.  Now, with support for Community Extensions in the DE 2.0, you can add supplemental  “layers” of business information and receive the same benefits whenever any EDXL message is sent. 

DE 2.0 Example Snippet
----------------------
The example below shows two extensions in use, one including earthquake information and one providing a local community term for urgency. (Note that the initial urgency tag in the snippet is from the main body of the DE 2.0 standard, which specifies a default set of typical xml enumerated values, and is the most interoperable; however, the extension mechanism allows local communities to add their own refinements.) The full example is available in the zip file.

....
   <urgency>Immediate</urgency>
    <severity>Minor</severity>
    <certainty>Observed</certainty>
    <ext:extension>
      <ext:community>http://www.mytestserver.org/layers/</ext:community>
      <ext:id>earthquake</ext:id>
      <ext:parameter>
        <ext:nameURI>http://www.mytestserver.org/layers/earthquake/Name</ext:nameURI>
        <ext:value>Earthquake1</ext:value>
      </ext:parameter>
      <ext:parameter>
        <ext:nameURI>http://www.mytestserver.org/layers/earthquake/Magnitude</ext:nameURI>
        <ext:value uom="http://www.mytestserver.org/layers/earthquake/RichterScale";>5.3</ext:value>
      </ext:parameter>
      <ext:parameter>
        <ext:nameURI>http://www.mytestserver.org/layers/earthquake/EventTime</ext:nameURI>
        <ext:value>2010-08-30T23:25:40+00:00</ext:value>
      </ext:parameter>
      <ext:parameter>
        <ext:nameURI>http://www.mytestserver.org/layers/earthquake/Depth</ext:nameURI>
        <ext:value uom="http://qudt.org/vocab/unit/MileInternational";>38.7</ext:value>
      </ext:parameter>
    </ext:extension>
    <ext:extension>
      <ext:community>http://mycommunity.org</ext:community>
      <ext:id>layer1</ext:id>
      <ext:parameter>
        <ext:nameURI>http://mycommunity.org/layer1/urgency</ext:nameURI>
        <ext:value>Low</ext:value>
      </ext:parameter>
    </ext:extension>
....