[Info-vax] Current state of file/disk encryption on VMS

[Stephen Hoffman]

On 2022-09-01 20:45:30 +0000, Alexander Schreiber said:

> Stephen Hoffman <seaohveh at hoffmanlabs.invalid> wrote:
>> 
>> If BACKUP is encrypting data before performing data compression, that's 
>>  a design bug in BACKUP.
> 
> Well, that is actually the right thing do to from a crypto security 
> point of view. Compressed files tend to have specified headers and 
> structures, which means that "compress, then encrypt" potentially 
> enables a nice automatic known plaintext attack. And I suspect that is 
> the reason it was done this way.

If your chosen encryption reveals your plaintext, your encryption needs 
help. Whether ghostly penguins, or otherwise.


-- 
Pure Personal Opinion | HoffmanLabs LLC