[Cryptography] Tempest and limits on receiving

[Dave Horsfall]

On Wed, 5 Apr 2017, Peter Gutmann wrote:

> That's only ones meant for the US market, or where the sales are small 
> enough that they don't do US vs. non-US versions, which is why many US 
> users would try and get the non-US models, except that US customs then 
> started seizing them at the border.  OTOH many of the US-targeted models 
> suffer from a series of strange design defects where they'll re-enable 
> full coverage when you cut a circuit trace or jumper (older models) or 
> press the right combination of keys (newer models).  For some odd reason 
> the magic nerve pinch always seems to leak in some manner soon after a 
> particular model is released.

This is similar to "region encoding" used on DVD players, where due to 
purely marketing reasons (not technical) DVDs meant for one region cannot 
be played in another.  In Australia at least (and likely NZ) the importers 
used to include a sheet describing the magic button pushes; these days, 
they are sold unlocked...

Oh, back in 1979 when I got my Amateur radio "ticket" I had to sign a 
"Declaration of Secrecy of Communications"; I've forgotten the exact 
wording, but it seems this hasn't been the case for some years now.

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."