I was trying to extract the staking address from an address and I was able to do that by using the bech32 decode, getting the last 56 bytes and encoding back again.
The question is: following this, I needed to add e1 (mainnet) or e0 (testnet) and it worked perfectly. The only thing though is that I don't know the reason. I mean, solving isn't enough, I wanted to understand why it's necessary to add those bytes as prefix.
Thank you.
The e comes from these address prefixes defined in the CDDL https://github.com/input-output-hk/cardano-ledger/blob/f2a783cf00911b7492e81dd6c7fb8a963f9ce8fe/eras/shelley/test-suite/cddl-files/shelley.cddl#L98
e equivalent in binary is 1110. The 0/1 is the part of the network ID defined in this part of the CDDL https://github.com/input-output-hk/cardano-ledger/blob/f2a783cf00911b7492e81dd6c7fb8a963f9ce8fe/eras/shelley/test-suite/cddl-files/shelley.cddl#L79
Combined they're the header that prefixes the payload defined here https://github.com/input-output-hk/cardano-ledger/blob/f2a783cf00911b7492e81dd6c7fb8a963f9ce8fe/eras/shelley/test-suite/cddl-files/shelley.cddl#L72
