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SIMID-1.0-simid-ssai-no-client

SIMID-1.0-simid-ssai-no-client

Linear SIMID creative with a Mezzanine but no progressive MediaFile cannot run in SSAI

InfoLinearIAB VAST 4.1 §1.1.2

Short answer

A Mezzanine file is the stitcher input. SIMID still needs a client player that can load the iframe. Streaming-only plus Mezzanine is the SSAI path with nothing for a device player to attach the creative to.

Why this matters in production

This is advisory context that still helps keep interactive delivery predictable and easier to debug across different SIMID-capable players. Linear SIMID issues affect the handshake between the primary video creative and the interactive layer. When these break, the ad often falls back to plain video or fails interaction entirely.

A Mezzanine file is the stitcher input. SIMID still needs a client player that can load the iframe. Streaming-only plus Mezzanine is the SSAI path with nothing for a device player to attach the creative to.

How to fix

Ship a progressive MediaFile alongside the Mezzanine so a client player can load the SIMID iframe after stitch.

Broader troubleshooting

If this rule is one part of a bigger SIMID delivery issue, start with the SIMID troubleshooting guide for a checklist covering iframe URLs, HTTPS, fallback media, and player support. If the XML is already clean, test the live tag: a JS file, frame headers, or a missing createSession will not show up in the catalog.

Invalid

<MediaFiles>
  <Mezzanine delivery="streaming" type="video/mp4" width="1920" height="1080">
    <![CDATA[https://cdn.example.com/mezz.mp4]]>
  </Mezzanine>
  <MediaFile delivery="streaming" type="application/x-mpegURL">
    <![CDATA[https://cdn.example.com/ad.m3u8]]>
  </MediaFile>
  <InteractiveCreativeFile type="text/html" apiFramework="SIMID">
    <![CDATA[https://example.com/creative.html]]>
  </InteractiveCreativeFile>
</MediaFiles>

Valid

<MediaFiles>
  <Mezzanine delivery="streaming" type="video/mp4" width="1920" height="1080">
    <![CDATA[https://cdn.example.com/mezz.mp4]]>
  </Mezzanine>
  <MediaFile delivery="progressive" type="video/mp4" width="1280" height="720">
    <![CDATA[https://cdn.example.com/ad.mp4]]>
  </MediaFile>
  <InteractiveCreativeFile type="text/html" apiFramework="SIMID">
    <![CDATA[https://example.com/creative.html]]>
  </InteractiveCreativeFile>
</MediaFiles>
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Other Linear rules

SIMID-1.0-simid-type-required<InteractiveCreativeFile apiFramework="SIMID"> must have type="text/html"SIMID-1.0-simid-url-empty<InteractiveCreativeFile apiFramework="SIMID"> must contain a non-empty URLSIMID-1.0-simid-url-https<InteractiveCreativeFile apiFramework="SIMID"> URL must use HTTPSSIMID-1.0-simid-url-data-htmlSIMID data: URI must declare text/htmlSIMID-1.0-simid-apiframework-caseapiFramework must be exactly "SIMID" (case-sensitive per SIMID §5)SIMID-1.0-simid-variable-duration-valuevariableDuration must be "true" when present on a SIMID InteractiveCreativeFileSIMID-1.0-simid-mediafile-requiredLinear SIMID ad must include a video/audio <MediaFile> alongside the interactive creativeSIMID-1.0-simid-interactive-startLinear SIMID creative on VAST 4.2+ should include an interactiveStart tracking event
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