: XML for video sitemaps: What value is expected for element "id", "type"? We've got an XML sitemap listing all of our magazine articles and videos, if the article contains a video. However, we

We've got an XML sitemap listing all of our magazine articles and videos, if the article contains a video. However, we got error messages in Google Search Console for the element "id" ("An unambiguous identifier for the video within a given identification context."). It says the attribute "type" was missing.

See sample markup from our XML sitemap:

<url>
<loc>http://www.chefkoch.de/magazin/artikel/1060,0/Chefkoch/Osterkuchen-Ostertorte-und-suesse-Kleinigkeiten.html</loc>
<lastmod>2016-05-10</lastmod>
<video:video>
<video:id>717</video:id>
<video:thumbnail_loc>http://static.xxx-xxx.de/xxx/videos/thumbs/717-org.jpg</video:thumbnail_loc>
<video:title>Osterkuchen, Ostertorte und süße Kleinigkeiten</video:title>
<video:description>In der Video-Reihe "Rikes Backschule" erfahrt ihr alles rund um Kuchen, Küchlein, Kekse und Desserts. In "Rikes Oster-Bäckerei" gibt es diesmal: Spiegeleikuchen.</video:description>
<video:content_loc>http://video.xxx-xxx.de/xxx/videos/717-video.mp4</video:content_loc>
<video:duration>257</video:duration>
<video:view_count>103862</video:view_count>
<video:publication_date>2015-03-16T13:06:13+01:00</video:publication_date>
<video:tag>Spiegeleikuchen</video:tag>
<video:tag>Rezept</video:tag>
<video:category>Kochen und Essen</video:category>
<video:uploader info="http://www.chefkoch.de">Chefkoch.de</video:uploader>
<video:family_friendly>yes</video:family_friendly>
<video:requires_subscription>no</video:requires_subscription>
<video:gallery_loc title="Backen">/magazin/6,277,0/Chefkoch</video:gallery_loc>
</video:video>
</url>

namespace definition: www.google.com/schemas/sitemap-video/1.1/sitemap-video.xsd
This is the part where "id" and "type" are defined in the xsd, but I don't quite get it:

<xsd:element name="id" minOccurs="0" maxOccurs="unbounded">
<xsd:annotation>
<xsd:documentation> An unambiguous identifier for the video within a given identification context. </xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:simpleContent>
<xsd:extension base="xsd:string">
<xsd:attribute name="type" use="required">
<xsd:annotation>
<xsd:documentation> The identification context. </xsd:documentation>
</xsd:annotation>
<xsd:simpleType>
<xsd:restriction base="xsd:string">
<xsd:enumeration value="tms:series"/>
<xsd:enumeration value="tms:program"/>
<xsd:enumeration value="rovi:series"/>
<xsd:enumeration value="rovi:program"/>
<xsd:enumeration value="freebase"/>
<xsd:enumeration value="url"/>
</xsd:restriction>
</xsd:simpleType>
</xsd:attribute>
</xsd:extension>
</xsd:simpleContent>
</xsd:complexType>
</xsd:element>

As far as I understand, the namespace defines: if using "id", the attribute "type" is required - but what do they mean by "The identification context."?

Can anyone give me an example as how to identify the ids context?