[tahoe-dev] zfec right for me?

[Ludovic Courtès]

Hello!

"Zooko O'Whielacronx" <zooko at zooko.com> writes:

> Again I think zfec
> augmented with your formatting improvements and libchop would be a
> good match for one another.

I’m not sure I fully understand what’s at stake, but I think an erasure
code could fit into libchop as an implementation of the “chopper”
interface (an object which, given a byte stream, returns a series of
blocks).

However, what’s missing in libchop is an “indexer” that knows that k out
of n blocks are sufficient, and something dual to choppers that
describes how blocks should be reassembled (erasure-coded blocks, here).
Currently the original stream is restored by simply concatenating blocks
that are fetched.

Alternatively erasure coding could be used at the level of the block
store—i.e., each block passed to ‘store_write’ would be erasure-coded,
resulting in n/k actual blocks written.  This is less work but
presumably also less fun.

I hope this makes sense...

Thanks,
Ludo’.