Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-13 Thread Nathan Wilcox
On Thu, Jun 11, 2015 at 12:55 PM, Aaron Voisine vois...@gmail.com wrote: A Header-PoW-verifying client could still be given all transactions in a recent block, from which it can see the in-band fees directly. You don't know the fees paid by any given transaction unless you also have all

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-11 Thread Mike Hearn
If we assume that transactions are being dropped in an unpredictable way when blocks are full, knowing the network congestion *right now* is critical, and even then you just have to hope that someone who wants that space more than you do doesn't show up after you disconnect. Yeah, my

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-11 Thread Tom Harding
On 6/11/2015 6:10 AM, Peter Todd wrote: On Wed, Jun 10, 2015 at 02:18:30PM -0700, Aaron Voisine wrote: The other complication is that this will tend to be a lagging indicator based on network congestion from the last time you connected. If we assume that transactions are being dropped in an

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-11 Thread Mike Hearn
Re: dropped in an unpredictable way - transactions would be dropped lowest fee/KB first, a completely predictable way. Quite agreed. No, Aaron is correct. It's unpredictable from the perspective of the user sending the transaction, and as they are the ones picking the fees, that is what

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-11 Thread Nathan Wilcox
On Wed, Jun 10, 2015 at 2:03 PM, Peter Todd p...@petertodd.org wrote: On Wed, Jun 10, 2015 at 02:00:27PM -0600, Nathan Wilcox wrote: On Wed, Jun 10, 2015 at 1:19 PM, Aaron Voisine vois...@gmail.com wrote: It could be done by agreeing on a data format and encoding it in an op_return

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-11 Thread Aaron Voisine
A Header-PoW-verifying client could still be given all transactions in a recent block, from which it can see the in-band fees directly. You don't know the fees paid by any given transaction unless you also have all it's inputs. Transaction inputs do not include an amount. You could however get

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-10 Thread Peter Todd
On Wed, Jun 10, 2015 at 02:00:27PM -0600, Nathan Wilcox wrote: On Wed, Jun 10, 2015 at 1:19 PM, Aaron Voisine vois...@gmail.com wrote: It could be done by agreeing on a data format and encoding it in an op_return output in the coinbase transaction. If it catches on it could later be

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-10 Thread Nathan Wilcox
On Wed, Jun 10, 2015 at 1:19 PM, Aaron Voisine vois...@gmail.com wrote: It could be done by agreeing on a data format and encoding it in an op_return output in the coinbase transaction. If it catches on it could later be enforced with a soft fork. Sounds plausible, except SPV protocols would

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-10 Thread Aaron Voisine
The other complication is that this will tend to be a lagging indicator based on network congestion from the last time you connected. If we assume that transactions are being dropped in an unpredictable way when blocks are full, knowing the network congestion *right now* is critical, and even then

Re: [Bitcoin-development] Proposal: SPV Fee Discovery mechanism

2015-06-10 Thread Aaron Voisine
Sounds plausible, except SPV protocols would need to include this coinbase txn if it's going to help SPV clients. Yes you'd either need a way to add those transactions to the bloom filter, or add/modify a p2p message to request it specifically. when you mention Sybil attack, I don't quite