Re: [Bitcoin-development] Version bits proposal
-BEGIN PGP SIGNED MESSAGE- Hash: SHA512 On 2015/5/26 21:48, Pieter Wuille wrote: here is a proposal for how to coordinate future soft-forking consensus changes: https://gist.github.com/sipa/bf69659f43e763540550 It supports multiple parallel changes, as well as changes that get permanently rejected without obstructing the rollout of others. Feel free to comment. As the gist does not support notifying participants of new comments, I would suggest using the mailing list instead. Hi Pieter. Thanks for posting the proposal. I think the concept itself is pretty solid. I know some people have been proposing alternate methods too. I hope they'll share here, assuming they haven't already. As is, my comments concern typos and general copy editing. - - Just speaking in general, I found the BIP to be a bit hard to read. AFAIK, the basic facts are accurate. I just found myself having to re-read certain passages two or three times. A little polish wouldn't hurt. For example, using the it pronoun can be confusing, such as multiple uses in the abstract. Specifying what it is (e.g., The proposed change relies on...) would really help. In addition, the way the W value is handled seems like it could be improved a bit. I know the wording is accurate. Seeing 1000 change to 1001 is still a little weird. - - In Multi-stage soft forks, I presume the second sentence should end as follows: [...] with additional validation rules that get enabled one by _one_. Depending on semantics, I'd consider changing one by one to incremental steps, but that's your call. - - I found the High bits section to be confusing at first. It looks like you chose to show everything as little endian data, matching what's actually in the block. My personal preference would be to represent the data, for readability purposes, as big endian. I doubt I'm the only one who finds big endian to be much easier to process mentally. - - Some sort of legend showing A, I, W, etc. would really help, as opposed to just running into them as one goes along. Otherwise, the alphabet soup can be a bit confusing. Thanks again. - -- - --- Douglas Roark Senior Developer Armory Technologies, Inc. d...@bitcoinarmory.com PGP key ID: 92ADC0D7 -BEGIN PGP SIGNATURE- Version: GnuPG/MacGPG2 v2.0.22 (Darwin) Comment: GPGTools - https://gpgtools.org iQIcBAEBCgAGBQJVZSx5AAoJEGybVGGSrcDXrYEQAOIrsggoZv0LdJHZjPGpEkeb 7ULhO4krZtQmKXjWDP0KnHAsFiyo5EOh1fYFRZz11OCqO4QmteTLPbodZFz47tKp tIYv5uc0qYhjfo5uLkzxuUky08VE4dUoELfqdbNciC45xHras7Wh/+KXc1a20Fib TaisWx9aL6VfPf7urM8b6mQ9XMba4YB3e2syAY8AA+qAEEP4DK2V6tuOQJD3kxP2 tbHtJnDvkDoXEY6tnL7fePo9X/IrlXLi8vNWGqPIf/hoiHmdvU+ORwHta7z9YeIO zi4LRs8n8sYmifY4nt6Wkkc1aoPsmpoXmI3tKgFM2h5bfdg0n3fN3K0nTMWtnR6z HUq8JhrQkZUP8uunN/23bt94FZolvnHTdL9YuWoyrlJ0gQri5YxV1BAN4hM9oCZy 1SqlSmFRplIFWu45q8/I5duDSphmA4NP2qc59QRjftcGYpNxmzaeSViiCDWzAjI9 qTLZgLTa/nf3TFN8oU8RwquGpwD82/fFo9V+uKdNGj79kdV8WOv4sa9q63OTVimJ w+r4l1gDZYyToe0heKtV2kL9Tt4HTn23bj7EvU+98uaKEpfWSP8a3BN9mPR7ork/ lNRGEGQ0tvkeDUzKy9IHuAjXo2XkKctbBRJwZJCGc5WW2sN0HdSu/GFPXrOOLf0J JXqeKpfaS0UriFXkxVHO =8uNL -END PGP SIGNATURE- -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
On Wed, May 27, 2015 at 12:29:28AM +0300, s7r wrote: What is wrong with the man testing some ideas on his custom branch? This is how improvements come to life. I saw in the BIPs some really interesting ideas and nice brainstorming which came from Peter Todd. Now, my question, if replace by fee doesn't allow me to change the inputs or the outputs, I can only add outputs... what can I do with this feature? If I sent a tx and want to replace it with a higher fee one, the higher fee one can only have maybe additional change addresses or another payment, if the inputs suffice? Do we have any real use cases? You're a bit mistaken there: standard RBF lets you change anything, and FSS RBF lets you modify inputs and add outputs and/or make the value of outputs higher. P.S. is it planned to include this by default in bitcoin core 10.0.3 or it will remain just on Peter's branch? Any significant change to mempool policy like RBF is very unlikely to be incorporated in the Bitcoin Core v0.10.x branch, simply because it'd be too large a change for a minor, mostly bugfix, release. Having said that, I already maintain a standard RBF branch for v0.10.x, and have been asked by a major minor to backport FSS RBF for v0.10.x as well. -- 'peter'[:-1]@petertodd.org 0b9e6c1ce35e6e06c01b1f381840bcd9297f307cb1e6aae8 signature.asc Description: Digital signature -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
[Bitcoin-development] Consensus-enforced transaction replacement via sequence numbers
Sequence numbers appear to have been originally intended as a mechanism for transaction replacement within the context of multi-party transaction construction, e.g. a micropayment channel. The idea is that a participant can sign successive versions of a transaction, each time incrementing the sequence field by some amount. Relay nodes perform transaction replacement according to some policy rule making use of the sequence numbers, e.g. requiring sequence numbers in a replacement to be monotonically increasing. As it happens, this cannot be made safe in the bitcoin protocol as deployed today, as there is no enforcement of the rule that miners include the most recent transaction in their blocks. As such, any protocol relying on a transaction replacement policy can be defeated by miners choosing not to follow that policy, which they may even be incentivised to do so (if older transactions provide higher fee per byte, for example). Transaction replacement is presently disabled in Bitcoin Core. These shortcomings can be fixed in an elegant way by giving sequence numbers new consensus-enforced semantics as a relative lock-time: if a sequence number is non-final (MAX_INT), its bitwise inverse is interpreted as either a relative height or time delta which is added to the height or median time of the block containing the output being spent to form a per-input lock-time. The lock-time of each input constructed in this manor, plus the nLockTime of the transaction itself if any input is non-final must be satisfied for a transaction to be valid. For example, a transaction with an txin.nSequence set to 0xff9b [== ~(uint32_t)100] is prevented by consensus rule from being selected for inclusion in a block until the 100th block following the one including the parent transaction referenced by that input. In this way one may construct, for example, a bidirectional micropayment channel where each change of direction increments sequence numbers to make the transaction become valid prior to any of the previously exchanged transactions. This also enables the discussed relative-form of CHECKLOCKTIMEVERIFY to be implemented in the same way: by checking transaction data only and not requiring contextual information like the block height or timestamp. An example implementation of this concept, as a policy change to the mempool processing of Bitcoin Core is available on github: https://github.com/maaku/bitcoin/tree/sequencenumbers -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
[Bitcoin-development] Version bits proposal
Hello everyone, here is a proposal for how to coordinate future soft-forking consensus changes: https://gist.github.com/sipa/bf69659f43e763540550 It supports multiple parallel changes, as well as changes that get permanently rejected without obstructing the rollout of others. Feel free to comment. As the gist does not support notifying participants of new comments, I would suggest using the mailing list instead. This is joint work with Peter Todd and Greg Maxwell. -- Pieter -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Version bits proposal
On Wednesday, May 27, 2015 1:48:05 AM Pieter Wuille wrote: Feel free to comment. As the gist does not support notifying participants of new comments, I would suggest using the mailing list instead. I suggest adding a section describing how this interacts with and changes GBT. Currently, the client tells the server what the highest block version it supports is, and the server indicates a block version to use in its template, as well as optional instructions for the client to forcefully use this version despite its own maximum version number. Making the version a bitfield contradicts the increment-only assumption of this design, and since GBT clients are not aware of overall network consensus state, reused bits can easily become confused. I suggest, therefore, that GBT clients should indicate (instead of a maximum supported version number) a list of softforks by identifier keyword, and the GBT server respond with a template indicating: - An object of softfork keywords to bit values, that the server will accept. - The version number, as presently conveyed, indicating the preferred softfork flags. Does this sound reasonable, and/or am I missing anything else? Luke -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Version bits proposal
It would also help to see the actual code changes required, which I'm sure will be much shorter than the explanation itself. On May 27, 2015 5:47 AM, Luke Dashjr l...@dashjr.org wrote: On Wednesday, May 27, 2015 1:48:05 AM Pieter Wuille wrote: Feel free to comment. As the gist does not support notifying participants of new comments, I would suggest using the mailing list instead. I suggest adding a section describing how this interacts with and changes GBT. Currently, the client tells the server what the highest block version it supports is, and the server indicates a block version to use in its template, as well as optional instructions for the client to forcefully use this version despite its own maximum version number. Making the version a bitfield contradicts the increment-only assumption of this design, and since GBT clients are not aware of overall network consensus state, reused bits can easily become confused. I suggest, therefore, that GBT clients should indicate (instead of a maximum supported version number) a list of softforks by identifier keyword, and the GBT server respond with a template indicating: - An object of softfork keywords to bit values, that the server will accept. - The version number, as presently conveyed, indicating the preferred softfork flags. Does this sound reasonable, and/or am I missing anything else? Luke -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] No Bitcoin For You
I think all the suggestions recommending cutting the block time down also suggest reducing the rewards to compensate. -- *James G. Phillips IV* https://plus.google.com/u/0/113107039501292625391/posts http://www.linkedin.com/in/ergophobe *Don't bunt. Aim out of the ball park. Aim for the company of immortals. -- David Ogilvy* *This message was created with 100% recycled electrons. Please think twice before printing.* On Tue, May 26, 2015 at 12:43 AM, gabe appleton gapplet...@gmail.com wrote: Sync time wouldn't be longer compared to 20MB, it would (eventually) be longer under either setup. Also, and this is probably a silly concern, but wouldn't changing block time change the supply curve? If we cut the rate in half or a power of two, that affects nothing, but if we want to keep it in round numbers, we need to do it by 10, 5, or 2. I feel like most people would bank for 10 or 5, both of which change the supply curve due to truncation. Again, it's a trivial concern, but probably one that should be addressed. On May 25, 2015 11:52 PM, Jim Phillips j...@ergophobia.org wrote: Incidentally, even once we have the Internet of Things brought on by 21, Inc. or whoever beats them to it, I would expect the average home to have only a single full node hub receiving the blockchain and broadcasting transactions created by all the minor SPV connected devices running within the house. The in-home full node would be peered with high bandwidth full-node relays running at the ISP or in the cloud. There are more than enough ISPs and cloud compute providers in the world such that there should be no concern at all about centralization of relays. Full nodes could some day become as ubiquitous on the Internet as authoritative DNS servers. And just like DNS servers, if you don't trust the nodes your ISP creates or it's too slow or censors transactions, there's nothing preventing you from peering with nodes hosted by the Googles or OpenDNSs out there, or running your own if you're really paranoid and have a few extra bucks for a VPS. -- *James G. Phillips IV* https://plus.google.com/u/0/113107039501292625391/posts http://www.linkedin.com/in/ergophobe *Don't bunt. Aim out of the ball park. Aim for the company of immortals. -- David Ogilvy* *This message was created with 100% recycled electrons. Please think twice before printing.* On Mon, May 25, 2015 at 10:23 PM, Jim Phillips j...@ergophobia.org wrote: I don't see how the fact that my 2Mbps connection causes me to not be a very good relay has any bearing on whether or not the network as a whole would be negatively impacted by a 20MB block. My inability to rapidly propagate blocks doesn't really harm the network. It's only if MOST relays are as slow as mine that it creates an issue. I'm one node in thousands (potentially tens or hundreds of thousands if/when Bitcoin goes mainstream). And I'm an individual. There's no reason at all for me to run a full node from my home, except to have my own trusted and validated copy of the blockchain on a computer I control directly. I don't need to act as a relay for that and as long as I can download blocks faster than they are created I'm fine. Also, I can easily afford a VPS server or several to run full nodes as relays if I am feeling altruistic. It's actually cheaper for me to lease a VPS than to keep my own home PC on 24/7, which is why I have 2 of them. And as a business, the cost of a server and bandwidth to run a full node is a drop in the bucket. I'm involved in several projects where we have full nodes running on leased servers with multiple 1Gbps connections. It's an almost zero cost. Those nodes could handle 20MB blocks today without thinking about it, and I'm sure our nodes are just a few amongst thousands just like them. I'm not at all concerned about the network being too centralized. What concerns me is the fact that we are using edge cases like my home PC as a lame excuse to debate expanding the capacity of the network. -- *James G. Phillips IV* https://plus.google.com/u/0/113107039501292625391/posts http://www.linkedin.com/in/ergophobe *Don't bunt. Aim out of the ball park. Aim for the company of immortals. -- David Ogilvy* *This message was created with 100% recycled electrons. Please think twice before printing.* On Mon, May 25, 2015 at 10:02 PM, Thy Shizzle thyshiz...@outlook.com wrote: Indeed Jim, your internet connection makes a good reason why I don't like 20mb blocks (right now). It would take you well over a minute to download the block before you could even relay it on, so much slow down in propagation! Yes I do see how decreasing the time to create blocks is a bit of a band-aid fix, and to use tge term I've seen mentioned here kicking the can down the road I agree that this is doing this, however as you say bandwidth is our biggest enemy right now and so hopefully by the time we exceed the capacity gained by the decrease
Re: [Bitcoin-development] Zero-Conf for Full Node Discovery
Very interesting Matt. For what it's worth, in future bitcoinj is very likely to bootstrap from Cartographer nodes (signed HTTP) rather than DNS, and we're also steadily working towards Tor by default. So this approach will probably stop working at some point. As breaking PorcFest would kind of suck, we might want a ZeroConf/Rendezvous solution in place so local LANs can capture Bitcoin traffic away from Tor (with some notification to the user, presumably). On Tue, May 26, 2015 at 7:47 AM, Matt Whitlock b...@mattwhitlock.name wrote: On Tuesday, 26 May 2015, at 1:15 am, Peter Todd wrote: On Tue, May 26, 2015 at 12:52:07AM -0400, Matt Whitlock wrote: On Monday, 25 May 2015, at 11:48 pm, Jim Phillips wrote: Do any wallets actually do this yet? Not that I know of, but they do seed their address database via DNS, which you can poison if you control the LAN's DNS resolver. I did this for a Bitcoin-only Wi-Fi network I operated at a remote festival. We had well over a hundred lightweight wallets, all trying to connect to the Bitcoin P2P network over a very bandwidth-constrained Internet link, so I poisoned the DNS and rejected all outbound connection attempts on port 8333, to force all the wallets to connect to a single local full node, which had connectivity to a single remote node over the Internet. Thus, all the lightweight wallets at the festival had Bitcoin network connectivity, but we only needed to backhaul the Bitcoin network's transaction traffic once. Interesting! What festival was this? The Porcupine Freedom Festival (PorcFest) in New Hampshire last summer. I strongly suspect that it's the largest gathering of Bitcoin users at any event that is not specifically Bitcoin-themed. There's a lot of overlap between the Bitcoin and liberty communities. PorcFest draws somewhere around 1000-2000 attendees, a solid quarter of whom have Bitcoin wallets on their mobile devices. The backhaul was a 3G cellular Internet connection, and the local Bitcoin node and network router were hosted on a Raspberry Pi with some Netfilter tricks to restrict connectivity. The net result was that all Bitcoin nodes (lightweight and heavyweight) on the local Wi-Fi network were unable to connect to any Bitcoin nodes except for the local node, which they discovered via DNS. I also had provisions in place to allow outbound connectivity to the API servers for Mycelium, Blockchain, and Coinbase wallets, by feeding the DNS resolver's results in real-time into a whitelisting Netfilter rule utilizing IP Sets. For your amusement, here's the graphic for the banner that I had made to advertise the network at the festival (*chuckle*): http://www.mattwhitlock.com/bitcoin_wifi.png -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] A suggestion for reducing the size of the UTXO database
On 05/25/2015 11:05 PM, Peter Todd wrote: On Mon, May 25, 2015 at 10:29:26PM +0200, Andreas Schildbach wrote: I see this behavior all the time. I am using the latest release, as far as I know. Version 4.30. The same behavior occurs in the Testnet3 variant of the app. Go in there with an empty wallet and receive one payment and wait for it to confirm. Then send a payment and, before it confirms, try to send another one. The wallet won't let you send the second payment. It'll say something like, You need x.xx more bitcoins to make this payment. But if you wait for your first payment to confirm, then you'll be able to make the second payment. If it matters, I configure the app to connect only to my own trusted Bitcoin node, so I only ever have one active connection at most. I notice that outgoing payments never show as Sent until they appear in a block, presumably because the app never sees the transaction come in over any connection. Yes, that's the issue. Because you're connecting only to one node, you don't get any instant confirmations -- due to a Bitcoin protocol limitation you can only get them from nodes you don't post the tx to. Odd, I just tried the above as well - with multiple peers connected - and had the exact same problem. It should work, I'm testing this regularly. Can you report an issue through the app and attach your log when this happens again? -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
I think this is a significant step forward. I suggest you also need to ensure that no inputs can be removed or changed (other than scriptsigs) -- only added. Otherwise, the semantics change too much for the original signers. Imagine a tx with two inputs from different parties. Should it be easy for party 1 to be able to eliminate party 2 as a contributor of funds? It's not difficult to imagine real-world consequences to not having contributed to the transaction. And unless you can think of a reason, tx-level attributes like nLocktime should not change either. The result would be something very like CPFP, but with the new inputs and outputs merged into the original tx, keeping most of the overhead savings you describe. It should be submitted to bitcoin/bitcoin because like most inconsistent relay policies, inconsistently deployed FSS RBF invites attacks (see https://gist.github.com/aalness/a78e3e35b90f52140f0d). Generally, to be kind to zeroconf: - Align relay and validation rules - Keep first-seen - Relay double-spends as alerts - Allow nLocktime transactions into the mempool a bit before they become final - ... It's not unlike making a best-effort to reduce sources of malleability. FSS RBF should be compatible with this if deployed consistently. On 5/25/2015 10:13 PM, Peter Todd wrote: Summary --- First-seen-safe replace-by-fee (FSS RBF) does the following: 1) Give users effective ways of getting stuck transactions unstuck. 2) Use blockchain space efficiently. without: 3) Changing the status quo with regard to zeroconf. The current Bitcoin Core implementation has first-seen mempool behavior. Once transaction t1 has been accepted, the transaction is never removed from the mempool until mined, or double-spent by a transaction in a block. The author's previously proposed replace-by-fee replaced this behavior with simply accepting the transaction paying the highest fee. FSS RBF is a compromise between these two behaviors. Transactions may be replaced by higher-fee paying transactions, provided that all outputs in the previous transaction are still paid by the replacement. While not as general as standard RBF, and with higher costs than standard RBF, this still allows fees on transaction to be increased after the fact with less cost and higher efficiency than child-pays-for-parent in many common situations; in some situations CPFP is unusable, leaving RBF as the only option. Semantics - For reference, standard replace-by-fee has the following criteria for determining whether to replace a transaction. 1) t2 pays fees than t1 2) The delta fees pay by t2, t2.fee - t1.fee, are = the minimum fee required to relay t2. (t2.size * min_fee_per_kb) 3) t2 pays more fees/kb than t1 FSS RBF adds the following additional criteria to replace-by-fee before allowing a transaction t1 to be replaced with t2: 1) All outputs of t1 exist in t2 and pay = the value in t1. 2) All outputs of t1 are unspent. 3) The order of outputs in t2 is the same as in t1 with additional new outputs at the end of the output list. 4) t2 only conflicts with a single transaction, t1 5) t2 does not spend any outputs of t1 (which would make it an invalid transaction, impossible to mine) These additional criteria respect the existing first-seen behavior of the Bitcoin Core mempool implementation, such that once an address is payed some amount of BTC, all subsequent replacement transactions will pay an equal or greater amount. In short, FSS-RBF is zeroconf safe and has no affect on the ability of attackers to doublespend. (beyond of course the fact that any changes what-so-ever to mempool behavior are potential zeroconf doublespend vulnerabilities) Implementation -- Pull-req for git HEAD: https://github.com/bitcoin/bitcoin/pull/6176 A backport to v0.10.2 is pending. An implementation of fee bumping respecting FSS rules is available at: https://github.com/petertodd/replace-by-fee-tools/blob/master/bump-fee.py Usage Scenarios --- Case 1: Increasing the fee on a single tx - We start with a 1-in-2-out P2PKH using transaction t1, 226 bytes in size with the minimal relay fee, 2.26uBTC. Increasing the fee while respecting FSS-RBF rules requires the addition of one more txin, with the change output value increased appropriately, resulting in transaction t2, size 374 bytes. If the change txout is sufficient for the fee increase, increasing the fee via CPFP requires a second 1-in-1-out transaction, 192 bytes, for a total of 418 bytes; if another input is required, CPFP requires a 2-in-1-out tx, 340 bytes, for a total of 566 bytes. Benefits: 11% to 34%+ cost savings, and RBF can increase fees even in cases where the original transaction didn't have a change output. Case 2: Paying multiple recipients in succession
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx. Thanks, -Danny On Mon, May 25, 2015 at 5:10 PM, Peter Todd p...@petertodd.org wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- 'peter'[:-1]@petertodd.org 134ce6577d4122094479f548b997baf84367eaf0c190bc9f -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
The general idea for replace by fee is that it would be restricted so as to make it safe, eg all the original addresses should receive no less bitcoin (more addresses can be added). The scorched earth game theory stuff (allowing removing recipients) is kind of orthogonal. Adam On 26 May 2015 at 19:22, Danny Thorpe danny.tho...@gmail.com wrote: What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx. Thanks, -Danny On Mon, May 25, 2015 at 5:10 PM, Peter Todd p...@petertodd.org wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- 'peter'[:-1]@petertodd.org 134ce6577d4122094479f548b997baf84367eaf0c190bc9f -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
What prevents you from writing a bad check using today's systems? On Tue, May 26, 2015 at 1:22 PM, Danny Thorpe danny.tho...@gmail.com wrote: What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx. Thanks, -Danny On Mon, May 25, 2015 at 5:10 PM, Peter Todd p...@petertodd.org wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- 'peter'[:-1]@petertodd.org 134ce6577d4122094479f548b997baf84367eaf0c190bc9f -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight.
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
See the first-seen-safe replace-by-fee thread Aaron Voisine co-founder and CEO breadwallet.com On Tue, May 26, 2015 at 11:22 AM, Danny Thorpe danny.tho...@gmail.com wrote: What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx. Thanks, -Danny On Mon, May 25, 2015 at 5:10 PM, Peter Todd p...@petertodd.org wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- 'peter'[:-1]@petertodd.org 134ce6577d4122094479f548b997baf84367eaf0c190bc9f -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight.
Re: [Bitcoin-development] Long-term mining incentives
Hello Mike, Are you aware of my proposal for network assurance contracts? Yes I am aware of that; sorry for not mentioning it. I think it is an interesting proposal, but I would not rely on it today, because it includes a large share of unproven social experiment. (Bitcoin too is a social experiment, but so far it has been working) But I agree with Gavin that attempting to plan for 20 years from now is ambitious at best. Bitcoin might not even exist 20 years from now, or might be an abandoned backwater a la USENET. I agree with that, but I don't think it can be used as a way to justify how decisions are made today. The opposition to block size increase comes from two things: (1) The perceived risk of increased centralization. (2) Long-term considerations on the need for fee pressure. I believe you and Gavin have properly addressed (1). Concerning (2), I think the belief that miners can eventually be funded by a fee market is wishful thinking. Thus, I am not against the proposed block size increase. However, the issue of long-term mining incentives remains. So far, the only proven method to incentivize mining has been direct block reward. The easiest solution to ensure long-term viability of Bitcoin would be to put an end to the original block halving schedule, and to keep the block reward constant (this is what Monero does, btw). That solution is inflationary, but in practice, users happen to lose private keys all the time. The rate of coins loss would eventually converge to whatever rate of emission is chosen, because the care people take of their coins depends on their value. Another solution, that does not break Bitcoin's social contract, would be to keep the original block halving schedule, but to allow miners to also redeem lost coins (defined as: coins that have not moved for a fixed number of years. Some time averaging of the lost coins may be needed in order to prevent non-productive miner strategies). That solution would create less uncertainty on the actual money supply, and better acceptability. I do not expect such a solution to be adopted before miner incentives become a problem. Neither am I attempting to predict the future; a completely different solution might be found before the problem arises, or Bitcoin might stop to exist for some other reason. However, if I had to decide today, I would choose such a solution, instead of relying on completely unproven mechanisms. More important, since we need to decide about block size today, I want to make it clear that my support is motivated by that long-term possibility. I believe that the we will need fee pressure argument can reasonably be dismissed, not because we don't know how Bitcoin will work in 20 years, but because we know how it works today, and it is not thanks to fee pressure. Thomas -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
[Bitcoin-development] please remove me from the list
Thanks. -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
I am not the one presenting this as some kind of novel attack on transactions in general. On Tue, May 26, 2015 at 1:43 PM, Raystonn rayst...@hotmail.com wrote: Trust, regulation, law, and the threat of force. Are you serious? On 26 May 2015 11:38 am, Allen Piscitello allen.piscite...@gmail.com wrote: What prevents you from writing a bad check using today's systems? On Tue, May 26, 2015 at 1:22 PM, Danny Thorpe danny.tho...@gmail.com wrote: What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx. Thanks, -Danny On Mon, May 25, 2015 at 5:10 PM, Peter Todd p...@petertodd.org wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- 'peter'[:-1]@petertodd.org 134ce6577d4122094479f548b997baf84367eaf0c190bc9f -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development --
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
On Tuesday, 26 May 2015, at 11:22 am, Danny Thorpe wrote: What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx. The First-Seen-Safe replace-by-fee presently being discussed on this list disallows fraudulent payment reversals, as it disallows a replacing transaction that pays less to any output script than the replaced transaction paid. -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
On Tue, May 26, 2015 at 5:54 PM, Tom Harding t...@thinlink.com wrote: It's not difficult to imagine real-world consequences to not having contributed to the transaction. I'm having a hard time. Can you help me understand a specific case where this makes a difference. It appears to be a gratuitous requirement; if I have another unused input that happens to be larger by the required fee-- why not just use it? The inherent malleability of signatures makes it unreliable to depend on the signature content of a transaction until its good and buried, regardless. And an inability to replace an input means you could not RBF for additional fees without taking change in more cases; there ought to be a benefit to that. -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
Trust, regulation, law, and the threat of force. Are you serious? On 26 May 2015 11:38 am, Allen Piscitello allen.piscite...@gmail.com wrote:What prevents you from writing a bad check using todays systems?On Tue, May 26, 2015 at 1:22 PM, Danny Thorpe danny.thorpe@gmail.com wrote:What prevents RBF from being used for fraudulent payment reversals? Pay 1BTC to Alice for hard goods, then after you receive the goods broadcast a double spend of that transaction to pay Alice nothing? Your only cost is the higher network fee of the 2nd tx.Thanks,-DannyOn Mon, May 25, 2015 at 5:10 PM, Peter Todd pete@petertodd.org wrote:On Tue, May 26, 2015 at 12:03:09AM 0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Lets suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 thats 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 thats 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so Im now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1s change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF Id simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- peter[:-1]@petertodd.org 134ce6577d4122094479f548b997baf84367eaf0c190bc9f -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50 applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50 applications Performance metrics, stats and reports that
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
You're the Chief Scientist of __ViaCoin__ a alt with 30 second blocks and you have big banks as clients. Shit like replace-by-fee and leading the anti-scaling mob is for your clients, not Bitcoin. Get the fuck out. Peter Todd - 8930511 Canada Ltd. 1214-1423 Mississauga Valley Blvd. Mississauga ON L5A 4A5 Canada https://www.ic.gc.ca/app/scr/cc/CorporationsCanada/fdrlCrpDtls.html?corpId=8930511 On 2015-05-26 00:10, Peter Todd wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
Please let's at least have some civility and decorum on this list. On Tue, May 26, 2015 at 1:30 PM, joli...@airmail.cc wrote: You're the Chief Scientist of __ViaCoin__ a alt with 30 second blocks and you have big banks as clients. Shit like replace-by-fee and leading the anti-scaling mob is for your clients, not Bitcoin. Get the fuck out. Peter Todd - 8930511 Canada Ltd. 1214-1423 Mississauga Valley Blvd. Mississauga ON L5A 4A5 Canada https://www.ic.gc.ca/app/scr/cc/CorporationsCanada/fdrlCrpDtls.html?corpId=8930511 On 2015-05-26 00:10, Peter Todd wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
Apologies if this has already been stated and I missed it, but: Can transactions in a buried block be overridden/replaced by RBF? Or is RBF strictly limited to transactions that have not yet been incorporated into a block? Thanks, -Danny On Mon, May 25, 2015 at 10:13 PM, Peter Todd p...@petertodd.org wrote: Summary --- First-seen-safe replace-by-fee (FSS RBF) does the following: 1) Give users effective ways of getting stuck transactions unstuck. 2) Use blockchain space efficiently. without: 3) Changing the status quo with regard to zeroconf. The current Bitcoin Core implementation has first-seen mempool behavior. Once transaction t1 has been accepted, the transaction is never removed from the mempool until mined, or double-spent by a transaction in a block. The author's previously proposed replace-by-fee replaced this behavior with simply accepting the transaction paying the highest fee. FSS RBF is a compromise between these two behaviors. Transactions may be replaced by higher-fee paying transactions, provided that all outputs in the previous transaction are still paid by the replacement. While not as general as standard RBF, and with higher costs than standard RBF, this still allows fees on transaction to be increased after the fact with less cost and higher efficiency than child-pays-for-parent in many common situations; in some situations CPFP is unusable, leaving RBF as the only option. Semantics - For reference, standard replace-by-fee has the following criteria for determining whether to replace a transaction. 1) t2 pays fees than t1 2) The delta fees pay by t2, t2.fee - t1.fee, are = the minimum fee required to relay t2. (t2.size * min_fee_per_kb) 3) t2 pays more fees/kb than t1 FSS RBF adds the following additional criteria to replace-by-fee before allowing a transaction t1 to be replaced with t2: 1) All outputs of t1 exist in t2 and pay = the value in t1. 2) All outputs of t1 are unspent. 3) The order of outputs in t2 is the same as in t1 with additional new outputs at the end of the output list. 4) t2 only conflicts with a single transaction, t1 5) t2 does not spend any outputs of t1 (which would make it an invalid transaction, impossible to mine) These additional criteria respect the existing first-seen behavior of the Bitcoin Core mempool implementation, such that once an address is payed some amount of BTC, all subsequent replacement transactions will pay an equal or greater amount. In short, FSS-RBF is zeroconf safe and has no affect on the ability of attackers to doublespend. (beyond of course the fact that any changes what-so-ever to mempool behavior are potential zeroconf doublespend vulnerabilities) Implementation -- Pull-req for git HEAD: https://github.com/bitcoin/bitcoin/pull/6176 A backport to v0.10.2 is pending. An implementation of fee bumping respecting FSS rules is available at: https://github.com/petertodd/replace-by-fee-tools/blob/master/bump-fee.py Usage Scenarios --- Case 1: Increasing the fee on a single tx - We start with a 1-in-2-out P2PKH using transaction t1, 226 bytes in size with the minimal relay fee, 2.26uBTC. Increasing the fee while respecting FSS-RBF rules requires the addition of one more txin, with the change output value increased appropriately, resulting in transaction t2, size 374 bytes. If the change txout is sufficient for the fee increase, increasing the fee via CPFP requires a second 1-in-1-out transaction, 192 bytes, for a total of 418 bytes; if another input is required, CPFP requires a 2-in-1-out tx, 340 bytes, for a total of 566 bytes. Benefits: 11% to 34%+ cost savings, and RBF can increase fees even in cases where the original transaction didn't have a change output. Case 2: Paying multiple recipients in succession We have a 1-in-2-out P2PKH transaction t1, 226 bytes, that pays Alice. We now need to pay Bob. With plain RBF we'd just add a new outptu and reduce the value of the change address, a 90% savings. However with FSS RBF, decreasing the value is not allowed, so we have to add an input. If the change of t1 is sufficient to pay Bob, a second 1-in-2-out tx can be created, 2*226=452 bytes in total. With FSS RBF we can replace t1 with a 2-in-3-out tx paying both, increasing the value of the change output appropriately, resulting in 408 bytes transaction saving 10% Similar to the above example in the case where the change address of t1 is insufficient to pay Bob the end result is one less transaction output in the wallet, defragmenting it. Spending these outputs later on would require two 148 byte inputs compared to one with RBF, resulting in an overall savings of 25% Case 3: Paying the same recipient multiple times For
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
It's just a mempool policy rule. Allowing the contents of blocks to change (other than by mining a competing chain) would be pretty much the largest possible change to Bitcoin's design -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
What is wrong with the man testing some ideas on his custom branch? This is how improvements come to life. I saw in the BIPs some really interesting ideas and nice brainstorming which came from Peter Todd. Now, my question, if replace by fee doesn't allow me to change the inputs or the outputs, I can only add outputs... what can I do with this feature? If I sent a tx and want to replace it with a higher fee one, the higher fee one can only have maybe additional change addresses or another payment, if the inputs suffice? Do we have any real use cases? P.S. is it planned to include this by default in bitcoin core 10.0.3 or it will remain just on Peter's branch? On 5/26/2015 11:30 PM, joli...@airmail.cc wrote: You're the Chief Scientist of __ViaCoin__ a alt with 30 second blocks and you have big banks as clients. Shit like replace-by-fee and leading the anti-scaling mob is for your clients, not Bitcoin. Get the fuck out. Peter Todd - 8930511 Canada Ltd. 1214-1423 Mississauga Valley Blvd. Mississauga ON L5A 4A5 Canada https://www.ic.gc.ca/app/scr/cc/CorporationsCanada/fdrlCrpDtls.html?corpId=8930511 On 2015-05-26 00:10, Peter Todd wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation w/o RBF costs you more than you save -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y
[Bitcoin-development] Bitcoin Survey Paper
Hi all, some time ago, we became interested in Bitcoin, but gathering relevant work and getting an overview was kind of painful. We took it as a sign that a survey paper on Bitcoin is desperately needed. Since then we observed the activities of the Bitcoin community. Recently we finished a technical report that is our attempt to contribute the lacking Bitcoin survey. Maybe it will be of interest to some of you: https://eprint.iacr.org/2015/464 Feedback is highly appreciated and would help to improve the quality of future revisions. Cheers, Florian. -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Bitcoin Survey Paper
Hi Florian! On 2015-05-26 15:54, Florian Tschorsch wrote: some time ago, we became interested in Bitcoin, but gathering relevant work and getting an overview was kind of painful. We took it as a sign that a survey paper on Bitcoin is desperately needed. Since then we observed the activities of the Bitcoin community. Recently we finished a technical report that is our attempt to contribute the lacking Bitcoin survey. Maybe it will be of interest to some of you: https://eprint.iacr.org/2015/464 Thanks for the work you (and your collegue) put into this paper! It is definitely a good step in the right direction! Feedback is highly appreciated and would help to improve the quality of future revisions. Do you know [1]? I've only glanced at both papers, but it seems that's also a research paper about Bitcoin co. [1] http://www.jbonneau.com/doc/BMCNKF15-IEEESP-bitcoin.pdf Apart from that, let me advertise myself a little bit. ;) In case you are interested in the difficulty mechanism (which you only mention briefly), I've recently written about it [2] (official publication) [3] (preprint without paywall). [2] http://link.springer.com/article/10.1007/s12083-015-0347-x [3] http://www.domob.eu/research/DifficultyControl.pdf Good luck with your further research! Yours, Daniel -- http://www.domob.eu/ OpenPGP: 1142 850E 6DFF 65BA 63D6 88A8 B249 2AC4 A733 0737 Namecoin: id/domob - https://nameid.org/?name=domob -- Done: Arc-Bar-Cav-Hea-Kni-Ran-Rog-Sam-Tou-Val-Wiz To go: Mon-Pri signature.asc Description: OpenPGP digital signature -- One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
Well so for example it could have an additional input (to increase the BTC paid into the transaction) and pay more to an existing change address and higher fee, or add an additional change address, and leave a larger fee, or if you had a right-sized coin add an additional input that all goes to fees. (As well as optionally tacking on additional pending payments to other addresses funded from the higher input). Adam On 26 May 2015 at 22:29, s7r s...@sky-ip.org wrote: What is wrong with the man testing some ideas on his custom branch? This is how improvements come to life. I saw in the BIPs some really interesting ideas and nice brainstorming which came from Peter Todd. Now, my question, if replace by fee doesn't allow me to change the inputs or the outputs, I can only add outputs... what can I do with this feature? If I sent a tx and want to replace it with a higher fee one, the higher fee one can only have maybe additional change addresses or another payment, if the inputs suffice? Do we have any real use cases? P.S. is it planned to include this by default in bitcoin core 10.0.3 or it will remain just on Peter's branch? On 5/26/2015 11:30 PM, joli...@airmail.cc wrote: You're the Chief Scientist of __ViaCoin__ a alt with 30 second blocks and you have big banks as clients. Shit like replace-by-fee and leading the anti-scaling mob is for your clients, not Bitcoin. Get the fuck out. Peter Todd - 8930511 Canada Ltd. 1214-1423 Mississauga Valley Blvd. Mississauga ON L5A 4A5 Canada https://www.ic.gc.ca/app/scr/cc/CorporationsCanada/fdrlCrpDtls.html?corpId=8930511 On 2015-05-26 00:10, Peter Todd wrote: On Tue, May 26, 2015 at 12:03:09AM +0200, Mike Hearn wrote: CPFP also solves it just fine. CPFP is a significantly more expensive way of paying fees than RBF, particularly for the use-case of defragmenting outputs, with cost savings ranging from 30% to 90% Case 1: CPFP vs. RBF for increasing the fee on a single tx -- Creating an spending a P2PKH output uses 34 bytes of txout, and 148 bytes of txin, 182 bytes total. Let's suppose I have a 1 BTC P2PKH output and I want to pay 0.1 BTC to Alice. This results in a 1in/2out transaction t1 that's 226 bytes in size. I forget to click on the priority fee option, so it goes out with the minimum fee of 2.26uBTC. Whoops! I use CPFP to spend that output, creating a new transaction t2 that's 192 bytes in size. I want to pay 1mBTC/KB for a fast confirmation, so I'm now paying 418uBTC of transaction fees. On the other hand, had I use RBF, my wallet would have simply rebroadcast t1 with the change address decreased. The rules require you to pay 2.26uBTC for the bandwidth consumed broadcasting it, plus the new fee level, or 218uBTC of fees in total. Cost savings: 48% Case 2: Paying multiple recipients in succession Suppose that after I pay Alice, I also decide to pay Bob for his hard work demonstrating cryptographic protocols. I need to create a new transaction t2 spending t1's change address. Normally t2 would be another 226 bytes in size, resulting in 226uBTC additional fees. With RBF on the other hand I can simply double-spend t1 with a transaction paying both Alice and Bob. This new transaction is 260 bytes in size. I have to pay 2.6uBTC additional fees to pay for the bandwidth consumed broadcasting it, resulting in an additional 36uBTC of fees. Cost savings: 84% Case 3: Paying multiple recipients from a 2-of-3 multisig wallet The above situation gets even worse with multisig. t1 in the multisig case is 367 bytes; t2 another 367 bytes, costing an additional 367uBTC in fees. With RBF we rewrite t1 with an additional output, resulting in a 399 byte transaction, with just 36uBTC in additional fees. Cost savings: 90% Case 4: Dust defragmentation My wallet has a two transaction outputs that it wants to combine into one for the purpose of UTXO defragmentation. It broadcasts transaction t1 with two inputs and one output, size 340 bytes, paying zero fees. Prior to the transaction confirming I find I need to spend those funds for a priority transaction at the 1mBTC/KB fee level. This transaction, t2a, has one input and two outputs, 226 bytes in size. However it needs to pay fees for both transactions at once, resulting in a combined total fee of 556uBTC. If this situation happens frequently, defragmenting UTXOs is likely to cost more in additional fees than it saves. With RBF I'd simply doublespend t1 with a 2-in-2-out transaction 374 bytes in size, paying 374uBTC. Even better, if one of the two inputs is sufficiently large to cover my costs I can doublespend t1 with a 1-in-2-out tx just 226 bytes in size, paying 226uBTC. Cost savings: 32% to 59%, or even infinite if defragmentation
Re: [Bitcoin-development] Cost savings by using replace-by-fee, 30-90%
That attitude and doxxing is not appropriate for this list. On Tue, May 26, 2015 at 4:30 PM, joli...@airmail.cc wrote: You're the Chief Scientist of __ViaCoin__ a alt with 30 second blocks and you have big banks as clients. Shit like replace-by-fee and leading the anti-scaling mob is for your clients, not Bitcoin. Get the fuck out. https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- Jeff Garzik Bitcoin core developer and open source evangelist BitPay, Inc. https://bitpay.com/ -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
On Tue, May 26, 2015 at 11:00 PM, Tom Harding t...@thinlink.com wrote: The bitcoin transaction is part of a real-world deal with unknown connections to the other parts I'm having a hard time parsing this. You might as well say that its part of a weeblix for how informative it is, since you've not defined it. not the case if paying parties are kicked out of the deal, and possibly don't learn about it right away. The signatures of a transaction can always be changed any any time, including by the miner, as they're not signed. A subset of parties to an Armory simulfunding transaction (an actual multi-input use case) could replace one signer's input after they broadcast it. They can already do this. Maybe the receiver cares where he is paid from or is basing a subsequent decision on it. Maybe a new output is being added, whose presence makes the transaction less likely to be confirmed quickly, with that speed affecting the business. The RBF behavior always moves in the direction of more prefered or otherwise the node would not switch to the replacement. Petertodd should perhaps make that more clear. But your maybes are what I was asking you to clarify. You said it wasn't hard to imagine; so I was asking for specific clarification. With Kalle's Proof of Payment proposed standard, one payer in a two-input transaction could decide to boot the other, and claim the concert tickets all for himself. The fact that he pays is not the only consideration in the real world -- what if these are the last 2 tickets? They can already do that. I'd argue that changing how an input is signed doesn't change the deal. For example if a different 2 of 3 multisig participants sign, those 3 people gave up that level of control when they created the multisig. Then why do you not argue that changing the input set does not change the weeblix? Why is one case of writing out a participant different that the other case of writing out a participant? Replacement is new - we have a choice what kind of warnings we need to give to signers of multi-input transactions. IMHO we should avoid needing a stronger warning than is already needed for 0-conf. How could a _stronger_ warning be required? -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
Thanks for the clarification. So, since RBF applies only to pending transactions in the mempool awaiting incorporation into a block, there is a window of opportunity in which the pending tx is incorporated into a block at the same time that the spender is constructing and publishing a replacement for that pending tx. The replacement transaction would be rejected by the peer network as a double spend because it conflicts with the now confirmed original tx, and the spender will have to go back and create a new stand-alone transaction to accomplish what they hoped to do with an RBF replacement. So an implementation that wishes to take advantage of RBF will still need to have a plan B implementation path to handle the corner case of a replacement tx being rejected as a double spend. Is this correct? I'm just trying to get my head around the implementation cost vs benefit of RBF in the context of my applications. Thanks, -Danny On Tue, May 26, 2015 at 2:27 PM, Pieter Wuille pieter.wui...@gmail.com wrote: It's just a mempool policy rule. Allowing the contents of blocks to change (other than by mining a competing chain) would be pretty much the largest possible change to Bitcoin's design -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
I think the point is the replacement tx spends the same inputs (plus additional inputs), so if the original tx is accepted, and your replacement rejected, thats good news - you dont have to pay the higher fee, the extra input remains unspent (and can be used later for other purpose) and the extra change address is unused. (If you had bundled extra transactions into the replacement, spending from the additional inputs, then you'll need to resubmit those as a separate transaction). (You have to keep in mind re-orgs so for example the original tx could be put into a block, and then that block could get reorged by another block that grows into a longer chain with the replacement tx in it (or vice versa)). Adam On 26 May 2015 at 23:09, Danny Thorpe danny.tho...@gmail.com wrote: Thanks for the clarification. So, since RBF applies only to pending transactions in the mempool awaiting incorporation into a block, there is a window of opportunity in which the pending tx is incorporated into a block at the same time that the spender is constructing and publishing a replacement for that pending tx. The replacement transaction would be rejected by the peer network as a double spend because it conflicts with the now confirmed original tx, and the spender will have to go back and create a new stand-alone transaction to accomplish what they hoped to do with an RBF replacement. So an implementation that wishes to take advantage of RBF will still need to have a plan B implementation path to handle the corner case of a replacement tx being rejected as a double spend. Is this correct? I'm just trying to get my head around the implementation cost vs benefit of RBF in the context of my applications. Thanks, -Danny On Tue, May 26, 2015 at 2:27 PM, Pieter Wuille pieter.wui...@gmail.com wrote: It's just a mempool policy rule. Allowing the contents of blocks to change (other than by mining a competing chain) would be pretty much the largest possible change to Bitcoin's design -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] First-Seen-Safe Replace-by-Fee
On 5/26/2015 4:11 PM, Gregory Maxwell wrote: On Tue, May 26, 2015 at 11:00 PM, Tom Harding t...@thinlink.com wrote: The bitcoin transaction is part of a real-world deal with unknown connections to the other parts I'm having a hard time parsing this. You might as well say that its part of a weeblix for how informative it is, since you've not defined it. For example, you are paying for concert tickets. The deal is concert tickets for bitcoin. Or you're buying a company with 3 other investors. not the case if paying parties are kicked out of the deal, and possibly don't learn about it right away. The signatures of a transaction can always be changed any any time, including by the miner, as they're not signed. Miners can't update the signature on input #0 after removing input #1. A subset of parties to an Armory simulfunding transaction (an actual multi-input use case) could replace one signer's input after they broadcast it. They can already do this. Replacement is about how difficult it is to change the tx after it is broadcast and seen by observers. Maybe the receiver cares where he is paid from or is basing a subsequent decision on it. Maybe a new output is being added, whose presence makes the transaction less likely to be confirmed quickly, with that speed affecting the business. The RBF behavior always moves in the direction of more prefered or otherwise the node would not switch to the replacement. Petertodd should perhaps make that more clear. But your maybes are what I was asking you to clarify. You said it wasn't hard to imagine; so I was asking for specific clarification. Pick any one maybe. They're only maybes because it's not realistic for them all to happen at once. With Kalle's Proof of Payment proposed standard, one payer in a two-input transaction could decide to boot the other, and claim the concert tickets all for himself. The fact that he pays is not the only consideration in the real world -- what if these are the last 2 tickets? They can already do that. Not without replacement, after broadcast, unless they successfully pay twice. I'd argue that changing how an input is signed doesn't change the deal. For example if a different 2 of 3 multisig participants sign, those 3 people gave up that level of control when they created the multisig. Then why do you not argue that changing the input set does not change the weeblix? Why is one case of writing out a participant different that the other case of writing out a participant? In the multisig input case, each signer already accepted the possibility of being written out. Peter Todd's proposal is in the spirit of not willfully making unconfirmed txes less reliable. I'm suggesting that multi-input signers should be included in the set of people for whom they don't get less reliable. Replacement is new - we have a choice what kind of warnings we need to give to signers of multi-input transactions. IMHO we should avoid needing a stronger warning than is already needed for 0-conf. How could a _stronger_ warning be required? We'd have to warn signers to multi-input txes instead of just warning receivers. -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
