FAQ

How Do I Download?

For individual files the best way is to browse and download with your favorite browser, got to the direcctory you want and right-click save.

For collections Bittorrent is your best options for getting a whole collection of files, and we prefer the qBittorrent client. Here is how:

Browse to a directory that includes the torrent files for the DEF CON year you are interested in, for example media.defcon.org/DEF CON 27/
Either double click on the torrent file you want to trigger qBittorrent, or download the torrent file and open manually in qBittorrent. Please keep the torrent seeding once it is complete to help everyone else downloading like you just did.

To subscribe to all torrent files use qBittorrent RSS subscription feature to add our RSS feed. qBittorrent will now start to download every torrent, about 1.1 TB worth, and once done will keep up to date on future torrents.

If you don't have or don't want to use bittorrent you can always go old skool with wget and automate your downloads. To discourage this due to our limited bandwidth I won't show you any examples how.

My torrent shows as no longer valid on the defcon.org tracker?

As new torrents are created with new and updated content, the old torrent file is removed from tracker.defcon.org and replaced with the fresh one. If you notice this then it is time to go download the new torrent file if you are not subscribed to our RSS feed, see above. If you are subscribed over the long term you will see multiple torrents for the same conference, but only one is tracking. It is up to you to decide when you remove the old torrents.

Note: Once in a while the directory a torrent is built off of changes. Files get renamed, spelling mistakes get fixed, or directory structures change. This leads to you having more files on your local disk than are needed. To correct this the safest thing to do is delete the torrent file and the directory of files it is associated with and re-download the torrent to get a fresh sync.

How Do I Stream The Videos?

Unfortunately no browser works with HEVC out of the box except Safari, and it needs the video files to include a special tag that no one else requires. We have just begun to work on how to automate tagging our entire archive, so native Safari support might take a few months.

Fow Windows10 Edge users it is simple. From the MS Store install this free CODEC. Once installed everything just works.

For Chrome, FireFox, the Tor Browser Bundle, and Brave we don't have a solution for you yet. We can't find a plug in or extension to make HEVC work. If you know of a solution please tell us!

What Formats Do You Use?

DT standardized on the HEVC codec for size efficency and GPU transcoding support for video files, FLAC, AAC, and Opus for audio, and where possible .rar compression for archives that include a data recovery record to prevent bit rot.

The amount of space savings from HEVC is too great to ignore, with average savings of 50-75 percent. We use two pass Average Bit Rate(ABR) encoding, but as of June 2020 we will switch to Variable Bit Rate (VBR). Once we purchase a new GPU that supports HEVC B frames we will try a value of 3.

How can I help?

You can help find new or missing content and let us know, help seed the torrent files, and help spread the word.

We have a dedicated forum for all things DEF CON, get involved with the community and make recommendations.

You can email us [info] @ [defcon.org] or on Twitter DM DEFCON information and links to any missing archives we don't currently host and we'll be happy to get them mirrored. Also, if you see errors or mistakes please let us know and we'll do our best to make corrections.