I do have _another_ logic analyzer....
For a while I worked at a company that made smart card readers. I wasn't working with those, but was on the same floor as people who were. The documentation on the encryption algorithm used was kept in a huge walk-in safe, with ridiculous security. One of those 'always two people, never one person alone with the data', dual keys, etc scenes.
In the readers, the module that contained the critical code was a potted block, that contained bare chips in ways that would break and lose the data if anyone tried to open it up.
In a video gambling game I did once, which used an FPGA to decrypt the program code on the fly as the CPU fetched it, the FPGA also contained logic that could detect whether there was a CPU emulator being used in place of the standard CPU. If there was, the FPGA deliberately immolated itself - large numbers of tristate buffers would try to fight each other, frying the chip in milliseconds.
I'm pretty sure that NVRAM will contain at least part of the option key data. There may be other parts in a flash memory also on the board. Once way to prevent successful removal would be to bump-mount a bare chip to the PCB _under_ the Dallas RAM-in-a-box, and also glue it to the underside of the Dallas thing. Desolder and remove the NVRAM, break the bare chip underneath. Board no longer works.
That's the kind of thing people who really care about data security actually do.
Whether Tek was like that around 2001 remains to be seen.
The 'hardware read-captures' method is typically countered by including staged-frequency-of-occurrence reads. Some data gets read all the time, some every few hours, some every few days, some every few months, etc. The aim is to _eventually_ try reading some data that the cracker never saw being read. If you find that the commonly read data is correct but the 'rare' data is bad, then you know you have an attempted crack. What you do then depends on what the lawyers will allow. If there are any.
And of course, in all anti-crack security systems, you make sure the entire system is 'busy', with huge amounts of camouflage (ie pointless, but _looks_ important) data flow. Filling up any watching LA buffers with junk.
I wonder if Tek mentioned when selling logic analyzers, that there's a critical part soldered in, that has only a 10 year lifetime? And will probably completely cripple the instrument when the potted-in battery dies.
Bet it's in the fine print somewhere, so no one can sue them.
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