Is Your Video the Real Life, or Just a Fantasy?

Use a checksum to verify the integrity of your downloaded video

With the rise of more advanced video editing software, it can be hard to separate fantasy from reality. As realistic as they may look on the big screen, dinosaurs and heroes with superhuman strength don’t really exist (yet). While these special effects belong in movies and TV shows, they have no place in video surveillance. With the new calculate checksum feature on MV video exports, you can rest easy knowing that no changes have been made to downloaded footage. When you rely on video for evidence, it is imperative to be able to ensure its authenticity.

Real or Fake? Pineapple gets eaten by dinosaurs in Meraki San Francisco office

 

How does it work?

A SHA-256 checksum is a 256-bit hash that uses an algorithm to create a file’s “signature.” This checksum can be calculated over and over again to the same result. However, once the file is changed in any way, this value changes. Read more about SHA-256 and other similar algorithms here.

For every generated MV export, Cisco Meraki provides you with the original file’s checksum for as long as the export is viewable on the dashboard. Every time you need to verify that any copy of the exported video is legitimate, you can use any terminal to calculate this copy’s checksum and compare it to the one provided on the dashboard. If they match, the video is identical. Otherwise, it has been corrupted or tampered with.

 

When do I need this?

While all Meraki MV exports contain a date and time stamp burnt into the video, there are a variety of circumstances in which additional verification provided by checksum may be desirable. A few examples include:

  • Chain of Custody: If you need to present a video clip as evidence and want to prove that it was not tampered with in any way.
  • Export Download: If you want to verify that your export download went smoothly and did not suffer any transmission errors, especially if it’s a large file that took several minutes to download.
  • File Transfer: If you want to verify that the stored video export has not been corrupted, especially if transferring the file between different locations.

For more information, check out our article on Sharing Video on the Documentation Portal.

Let us know how you plan on using this feature in the Meraki Community.