It looks like we could use a tag for format preserving encrytion (even if there is only one question yet - so maybe not). The full name is too long, what about format-preserving? fpe seems a bit too short, though.

@Ninefingers I have seen that. I am doing discrete but insistent promotion toward researchers which I deem to be good targets.

"Good targets" = "people who are competent both in crypto and in the 'explaining'"

@PaŭloEbermann If there is a format-preserving tag, there should also be short-blocks as a synonym.

(FPE usually comes from the need of "a block cipher with short blocks")

@ThomasPornin Good point. (I'll not yet create it, maybe someone else has something to say, and for a single question it might not even be needed at all.)

@ThomasPornin That's a good point.