Haha I came here to ask the same question. This "SIV" mode is silly and breaks down completely when encrypting more than 2^32 IDs. Your proposal is not only f

Haha I came here to ask the same question. This "SIV" mode is silly and breaks down completely when encrypting more than 2^32 IDs. Your proposal is not only faster, but also safer. AES is a strong pseudorandom permutation, the 00000000 padding is a perfectly fine integrity check.