SONY Blu-ray "dummy_x.dat" files

[setarip_old]

In addition to the "BDMV" and "CERTIFICATE" folders, and the PS3 update folders/files, the root directory of "Zookeeper" contains two files, "dummy_f.dat" 102,400Kb and "dummy_r.dat" 3,301,581Kb.

They contain nothing but zeros ("00"), not even headers.

Omitting them from disc compression has no noted negative effect.

Does anyone KNOW what purpose, if any, these files serve?

[Ghitulescu]

Probably they fill in the space otherwise left void.
Why?
To "move" the real content towards the periphery (higher access speeds), to separate real content one from the other, to balance the diameters of the two layers (if it's a dual layer)...
Some dummy files were used as a sort of copy protection on some DVDs (will it work on BDs???).
Maybe not all authoring suites have the possibility to physically arrange the content.

These are only suppositions, of course.

[setarip_old]

Again:

Omitting them from disc compression has no noted negative effect. (So, no, it's not ancient copy protection)

Does anyone KNOW what purpose, if any, these files serve?

BTW - Although I've seen many examples of apparent vestiges of authoring programs appearing on finalized commercial discs (Warner discs, in particular, come to mind), this is the first example of these specific filetypes/content I've seen in the MANY Blu-ray discs I've dealt with...

[ron spencer]

dummy would imply dummy data...used to test something. What who knows.....

[hello_hello]

Because there's PS3 updates on the disc, and because the PS3 is not unknown for using dummy files as part of an update or copy protection, I'd be tempted to speculate they're only relevant to the PS3.... if it was okay to speculate rather than actually know. ;)