Re: building compatible zip files "by hand" that are encrypted and compressed

On 27 Sep 2003 at 17:35, Ed Fair wrote:

> Greg,
> I do have a follow-up question for you.  Supposing I
> do encrypt with AES and compress with (deflate?) on
> the client before uploading.  I will then have a
> collection of already compressed and already encrypted
> files.

No, you'd have a collection of encrypted files that have been made 
*larger* by attempting to compress them.

Any encryption scheme worth the name will produce files that are 
essentially incompressible. To do both, you have to compress first 
and encrypt afterwards.