[cap-talk] Horton at HotSec '07: How broadly object/capability?

[Mark Miller]

> To be fair, it certainly is easier to install software on every
> computer than to wrap every tree in a membrane

Virtually all biological creatures already are wrapped in membranes.
Indeed, this is where the analogy comes from. (The only exception I
can think of is prions.)

Multicellular creatures are usually wrapped in two levels: not only do
all their cells have membranes, the cells on their outer surface
usually specialize in acting as a barrier/filter between the outer
world and the protected inner world, so that the rest of the cells can
rely on a less hostile environment. In us, that's skin and GI lining.
In trees, the protective membranes even includes bark. Biology has
been playing these games a lot longer than we have.

The most salient differences between the physical, biological, and
computational worlds:
* In the physical world, many kinds of attack involve "work factor" --
some marginal cost to the attacker. In the computational biological
worlds, the marginal costs of an attack is paid by the victim.
* In the physical and biological worlds, barriers can only resist, not
prevent, attack. They are imperfect and costly. Computational barriers
can be perfect and cheap.

For more, see "Comparative Ecology: A Computational Perspective" at
<http://www.agorics.com/Library/agoricpapers.html>.

-- 
Text by me above is hereby placed in the public domain

    Cheers,
    --MarkM