Hi everyone, very briefly:

I'm doing some academic research in this direction: to develop a reliable technique to remotely perform software upgrades of router boards.

Please note all the big challenges:
1) I assume that management can be done ONLY "in-band", for example by ssh over wireless channel. So, if you bring down the wireless interface you're f*ked.
2) By "software upgrades" I mean anything: from changing a single comma in the motd to upgrading the kernel, from replacing the wireless driver to changing the file system completely.
3) The system has to be "disaster proof". In case a change makes the board unreachable or frozen, then it automatically rollback to the latest working configuration (or a specified failback situation).

I'm picking OpenWRT as environment because I already use it in my testbed scenario (see http://www.tegola.org.uk) and obviously because it's dramatically flexible and because I like it

I'm wondering if you have any specific pointers I should evaluate as a starting comparison, for example known approaches of other firmware platforms (inc. commercial ones)...

Thanks
mino