Proof-of-Data availability
To address the issue of data availability and minimize data overhead , there are methods that allow for verifying large amounts of data without requiring every participant to download the entire blockchain. One such method is Proof-of-Data availability (PoDa), introduced by #syscoin.
In the first stage of PoDa, the data is
replicated, which allows any node to copy it. This ensures that the data is widely distributed throughout the network. It's assumed that if there are enough nodes, at least one will be honest (the
Honest Minority Assumption). Therefore, the data will always remain accessible because the honest node can provide it.
After a short period, the replicated data is
archived and removed from the main chain, but it remains available off-chain, assuming Honest Minority Assumption. Network participants can
request the data from replicating nodes at any time. This means the data is always available and cannot be censored, making data withholding attacks complex.
