[SystemSafety] Fwd: "Protected" Environments

[Olwen Morgan]

On 11/11/2018 06:00, Peter Bernard Ladkin wrote:

<snip>
> Can anyone name any civil system which has successfully established a 
> "security environment" (it looks a lot like a "zone" from IEC 62443 
> but apparently it is not), within which safety engineers can perform 
> safety analyses and design safety functions assuming everything is 
> cybersecure?
<snip>


To put this in another perspective, cybersecurity depends, among other 
things, on robust cryptography. Currently the strength of our 
cryptographic systems rests on the premise that nobody can break 
public-key ciphers. As it happens, I know a bit about the history of 
cryptography. Throughout that history ciphers have been broken whose 
inventors believed they were secure simply because they themselves 
didn't know how to break them. As Churchill said, "Those who do not 
learn from history are condemned to repeat it."


Just a thought.

olwen