Short on time, but I&#x27;ll say she&#x27;s looking in the right idea in general. This idea has actually been done before. Removable firmware part used to happen in older machines, too.<p><i>Far as I know</i>, I came up with it first with a proposal on Schneier&#x27;s blog, etc to put both the CPU and trusted state on a stick or card you inserted into a machine containing only peripherals maybe with RAM. Research CPU&#x27;s at the time had RAM encryption&#x2F;integrity to make it untrusted. I was thinking PC Card rather than stick due to EMSEC, storage, and cost issues. I&#x27;ll try to find the link later today.<p>It was actually inspired by foreign, airport security compromising stuff. People asked me to develop a convenient solution. So, real problem was physical access to the trusted components. That access couldn&#x27;t happen but can&#x27;t keep all our gear with us or away from inspection. A simple chip or PC Card they carried on would be better. The chassis, from laptop to whatever, they could acquire in country or ship separately with inspection. I further imagined a whole market popping up supplying both secure sticks&#x2F;cards and the stuff you plug them into. Inspiration for that was iPod &amp; its accessories like docks. One more part was that each user could determine how much protection, from tamper-evidence to EMSEC, to apply to their trusted device.<p>As it sometimes happens, another company showed up with government backing IIRC and R&amp;D on security devices. Their proposed portfolio was very similar. They undoubtedly started patenting all of it. This created a second risk for anyone attempting what I or now Joanna is attempting: a greedy, defence-connected, third party legally controlling pieces of your core business. They usually just rob people but I predicted on Schneier&#x27;s blog &amp; later here in a heated debate that they could attempt to change or get rid of the product using their patents. Especially true if a proxy for an intelligence agency. We might have just seen that happen with Apple over iMessage but I can&#x27;t be sure. Anyway, do know there&#x27;s both prior art and probably patents on these concepts in defense industry.<p>So, it was a cool concept. It was one of those I was proudest of given it collapsed problems with all kinds of devices to design and protection of one component. That&#x27;s basic Orange Book-era thinking I try to remember. Unfortunately, after much debate with marketing types, we determined there was a chicken and the egg problem with these [at the time]. The NRE cost would be high to the point you&#x27;d want to be sure there was a demand for thousands of them plus people willing to pay high unit prices. Custom laptops were often closer to $10,000 than $3,000 if low volume. My greater market idea was chicken-and-the-egg times a million. That plus risk of 3rd party patents made me back off the idea as nice but not practical.<p>Since then, what&#x27;s changed is dramatically lower cost for homebrew hardware or industrial prototyping. Projects like Novena show it can probably be done for lower NRE than before. However, this is security-critical design that needs strong expertise in both hardware (esp analog&#x2F;RF) and Intel x86. That will up the NRE and odds of them screwing up. ARM or MIPS (&quot;cheaper ARM&quot;) might be easier to do but still need HW expert and significant NRE.<p>So, there&#x27;s my take. It&#x27;s a good idea that two of us in security industry already fleshed-out with removable firmware being proven in ancient mainframes. Serious marketing obstacles to getting this done and done securely. A high-level design for the technology, as I did, is pretty straight-forward and will teach one many lessons. It was a good learning experience if nothing else.