The <Extended_Metadata> field will allow organizations to store user defined values within the metadata record without reusing existing GCMD defined metadata fields.

• The <Extended_Metadata> field is optional and may not be repeated.
• The <Metadata> field can be repeated.
• If the <Metadata> field is used, the <Name> field is required.
• The <Group> field can use a unique name for an organization and a reverse URL scheme is recommended. May contain up to 1024 characters.
• If a <Group> field is not provided, then it will be assumed to be in an "uncategorized" group. Internally GCMD software will treat an undefined group as "*".
• The <Name> field may contain up to 1024 characters.
• <Name> fields must be unique in the global group. If two organizations use the same <Name> field for different usages, one must define their property within the <Group> field.
• The <Value> field and <Group> field are highly recommended and may contain binary data within a <![CDATA [ ] ]> tag.
• The <Value> field is optional and assumed to be "yes".

<Metadata>
<Group>gov.nasa.gsfc.gcmd</Group>
<Name>metadata.uuid</Name>
<Value>93c81800-c33f-4bd7-bdaf-de314425e2d2</Value>
</Metadata>

<Metadata>
<Group>gov.nasa.gsfc.gcmd</Group>
<Name>metadata.extraction_date</Name>
<Value>2012-11-15 12:08:24</Value>
</Metadata>

<Metadata>
<Group>gov.nasa.gsfc.gcmd</Group>
<Name>metadata.keyword_version</Name>
<Value>7.0</Value>
</Metadata>