and it involves stateful distribution of mapping information. A very different beast from GSE, and it sets off my stateful=bad alarm.
Actually this wouldn't be a problem at all since we have to keep this exact same state anyway in order to map the other way around for sending packets back.
I don't think it's a coincidence that there hasn't been any progress with GSE for five years or so. In theory, GSE can work without a mapping mechanism, but this opens the door to security problems. So in practice we need to keep state to know whether there is a valid locator <-> identifier mapping to avoid trivial identity theft. And if we accept that, we may as well remove the whole globally unique lower 64 bit thing as it just breaks too much stuff without any real benefits at this point.Again, not in GSE as I understand it.