Re: X.509 certificates on small micros?

But - I'm not quite getting the idea I'm afraid - in the description
above is the "8-bitter" on the System A _or_ System B? In other words,
on "8-bitter" are you going to perform the private key _or_ the public
key RSA operation?

The answer to this is "yes". In short, various Systems A and B already exist today, and they're currently 8-bit (mostly). I want to introduce this new certificate >infrastructure, and will tinker with the "who does what" question to minimize the number of devices that need massive hardware upgrades. If it turns out we need to >move to tiny ARMs on everything, that is doable, though - a small Cortex-M3 can be had for around $0.80 these days...

Hmm, I don't understand the 'yes' answer to 'this OR that?' question,
sorry ;)

Can't say for sure for the OP, but probably very similar to us.
System A is a 8 bit device and System B is a 64/128/whatever bits
server.
The 8 bitter authenticates against the server key. (don't want to say
public key here).
.