On Thu, 12 Jan 1995, Jonathan Rochkind wrote:
Of course, we're not just dealing with text. So the scheme has got to be changed a bit so as to be able to detect unencrypted GIFs, and mu-law files, and as yet to be determined unknown files. I don't know enough about what's being talked about to know if this entropy detecting stuff will generalize to non text files.
Graphics files are already compressed, so they pass the entropy test, but they start with a distinctive header. The best way to stop graphics would be a volume limit per apparent source and per apparent destination. To program that is a bit like hard work. --------------------------------------------------------------------- We have the right to defend ourselves and our property, because of the kind of animals that we http://nw.com/jamesd/ are. True law derives from this right, not from James A. Donald the arbitrary power of the omnipotent state. jamesd@netcom.com