[omazurov]

I'm not talking about CD-ROMs or immediate availability in any form. How would you encode a petabyte (for a starter) with LDPC/Turbo? Not available right away but accumulated over months with no predefined upper limit? Computational cost remains an important factor but other requirements take over.

[dragontamer]

> How would you encode a petabyte (for a starter) with LDPC/Turbo?

I'm fairly certain that particular problem you're asking for is solved by "fountain LDPC codes", and can't be solved by RS by any methodology.

RS is limited to its block size (in this case, 2^20 sized block), which can be "extended" by interleaving the codes (with various kinds of interleaving). But interleaving a petabyte of data is unreasonable for RS.

I admit I'm not hugely studied in practical codes, mostly just got the college-textbook understanding of them.

[omazurov]

I can only repeat my initial statement:

> Multi-dimensional RS codes are an easy way to get to an absurdly huge size for real.

"Multi-dimensional" may mean 3,4,..,10 dimensions. "Absurdly huge" means a petabyte and beyond. "For real" means practical recovery of swaths of lost or damaged data. "Fountain LDPC codes" are essentially one-dimensional. Extending them to the ability of recovering an annihilated data center would make them impractical. Making them multi-dimensional would make them inferior to RS (which is still MDS in every single dimension).