Say you generate a child key using the path m/6'/4'/7'/99'/0/196, which is what your proposed path structure would be, and it results in the address 1DpY7PtPVURvjrGsdAjbZAZ7cL9GD8tc5w.
When the wallet notices a transaction in the blockchain that has 1DpY7PtPVURvjrGsdAjbZAZ7cL9GD8tc5w as an output, it's going to have to lookup the address within its database to get the values 6/4/7/99/0/196, as there's no way to retrieve them from just the address. So technically, you might as well just use m/account'/change/index if using hardened child keys, or m/change/index if not, as recommended, because the wallet will still function the exact same way. Matt On 06/20/2015 06:31 AM, Matt Smith wrote: > I'm not sure I understand your question about the need to store paths in > the wallet database -- there's no way to infer the path of an address > inside an HD wallet from the address alone (short of an exhaustive > search), and HD wallets need to store either the paths, addresses, or > both that have been previously derived/used to monitor the blockchain > usefully, but those facts aren't new or specific to this path format. > > The motivation for this path structure over standard bip44 is that it > separates the concept of network (or which blockchain I'm using) and > coin_type (or what kind of thing I'm sending over that blockchain). > > This is useful, for example, if I want to import a wallet into my > application and I know that an account was in use at > > m/##'/0'/99'/0' > > where 99 is the identifier for, say, counterparty - I only need to check > the addresses derived below that path for balances against > counterpartyd. It may be worth pointing out that I expect multisig HD > wallet imports to require master keys and a list of account paths – not > a list of addresses, as it's very possible that a new address could be > derived between the time when the wallet data was exported and when it > will be imported. > > This use case might be very specific to our model, but the reason I > figured we should request a BIP # for this is that to start using it, we > need to pick a number for the purpose field and don't want to do it > arbitrarily (and risk having to change it later) or overload 44 (which > would be misleading). > > Did I either a) answer or b) misunderstand your questions? > -- > Matt Smith | Gem > https://gem.co | GH: @thedoctor > > > > On 6/19/15 2:25 PM, Matt @ Envrin Group wrote: >> Hi Matt, >> >> I think your best bet is probably just push it out privately via blog >> post / Github, and see if it gains any traction with other developers. >> >> I'm a little uncertain as to the relevance though. All those variables >> (purpose, network, asset_type, account, change, index) need to be stored >> internally within the wallet database, as there's no way to retrieve the >> path used from just the address, correct? In that case, what's the >> meaning of that exact path structure when a) it can't be retrieved from >> just the address, and b) the values will be stored internally within the >> wallet when you lookup the address. >> >> Matt ------------------------------------------------------------------------------ _______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
