All formal data elements in DASH7 Mode 2 are contained within the integrated filesystem. Informal data elements may exist in implementation, but they must at some point connect back to the standardized filesystem.
ISFB Main Article
ISFB stands for Indexed Short File Block. It is searchable through M2QP commands. It contains up to 256 individual files, each up to 255 bytes in length. The lower 16 files (0-15) contain the Mode 2 registry (an unofficial name). Files 16-31 are reserved for official definition, but most of them are currently undefined. The rest of the files are available for any type of usage.
ISFSB Main Article
ISFSB stands for Indexed Short File Series Block. It is a list of ISFB file IDs, each list being 0-16 bytes in length. In usage, ISFSB files are used as batch pointers to ISF files.
GFB Main Article
GFB stands for Generic File Block. GFB files are unstructured, 0-65535 bytes in length. They are optional, and many Mode 2 applications do not actually implement the GFB.