That's just LDPC but not as extreme. If you're going to "nest" erasure codes, might as well make them XOR-based (fastest operation on modern CPUs and/or hardwa

That's just LDPC but not as extreme. If you're going to "nest" erasure codes, might as well make them XOR-based (fastest operation on modern CPUs and/or hardware), calculate a randomization scheme that has very-very high probability (99.9%+) of fixing errors, and other such benefits. To provide assurances that you have enough LDPC, you then run LDPC on your LDPC-check bits. Then you run LDPC on your LDPC-LDPC-check bits. Then you run LDPC on your LPDC-LDPC-LDPC-check bits, until you've got the target probability / chance of fixing errors that you desire. -------- LDPC's brilliance is that XOR-as-erasure-code is exceptionally fast, and this "repeated hierarchy" of error-correction codes leads to high-probabilities (99.9999%+) of successful correction of erasures.