Re: [Bitcoin-development] MtGox blames bitcoin

2014-02-10 Thread Isidor Zeuner
try to create pressure by suspending money withdrawals until the TCP/IP protocol is changed to match their preferences. Best regards, Isidor Zeuner -- Managing the Performance of Cloud-Based Applications Take advantage

Re: [Bitcoin-development] Why are we bleeding nodes?

2014-05-20 Thread Isidor Zeuner
In my opinion, the number of full nodes doesn't matter (as long as it's enough to satisfy demand by other nodes). Correct. Still, a high number of nodes has a few other benefits: 1) The more nodes there are, the cheaper it should be to run each one, given that the bandwidth and CPU

Re: [Bitcoin-development] Proposals for improving Bitcoin mining decentralization

2014-06-17 Thread Isidor Zeuner
quote: https://en.bitcoin.it/wiki/Getblocktemplate is supposed to solve most of the pooling-centralization problems. Unfortunately, it is opt-in, and GHash.io doesn't support it. Also most miners don't care and don't do the work to set it up. To do transaction inclusion themselves, they'd

Re: [Bitcoin-development] instant confirmation via payment protocol backwards compatible proto buffer extension

2014-06-17 Thread Isidor Zeuner
quote: On 6/16/14, Mike Hearn m...@plan99.net wrote: If they decide to change to something like highest-fee-always-wins, then they (again) centralise things by forcing all instant transactions to pay GreenAddress and its competitors money - much though I like your product Lawrence, let's

Re: [Bitcoin-development] instant confirmation via payment protocol backwards compatible proto buffer extension

2014-06-17 Thread Isidor Zeuner
quote: Mike Hearn, why don't we just have all nodes report attempted double spends through the node network. No need to involve the miners at all really, or do your suggestion but also report the double spend attempt. By waiting maybe 10-60 seconds (instead of 10 minutes for first conf),

Re: [Bitcoin-development] 0 confirmation txs using replace-by-fee and game theory

2014-06-18 Thread Isidor Zeuner
quote: [...] On 4/24/14, Chris Pacia ctpa...@gmail.com wrote: It would work but it's an ugly hack IMO. What do people do if they don't have extra to pay when making a purchase? I have 200 mbtc and want to buy a 200 mbtc phone but I can't because I need 400 mbtc. Sucks for me. I would

Re: [Bitcoin-development] Bitcoin Protocol Specification

2014-07-02 Thread Isidor Zeuner
Hello Krzysztof, [...] As before, it can be found under: http://enetium.com/resources/Bitcoin.pdf I hope it will prove useful to the community and thank in advance for any further improvement proposals. I think it's great work and provides a good reference for those who want to get some

[Bitcoin-development] Proposal: PoW-based throttling of addresses (was: Outbound connections rotation)

2014-08-20 Thread Isidor Zeuner
Hi there, quote: [...] If two distinct transactions (with unrelated bitcoin addresses) come from the same set of 8 peers, the attacker can conclude that they originated from the same user. This gives another method (in addition to transaction graph analysis) for an attacker to link different

Re: [Bitcoin-development] Proposal: PoW-based throttling of addresses (was: Outbound connections rotation)

2014-08-23 Thread Isidor Zeuner
Hi Mike, thanks for your assessment. Please find my replies in-line: Misbehaving addresses can have their connecting difficulty scaled up, which should make it uneconomic to try to DoS the usage of Tor exit nodes for connecting to Bitcoin. You can't solve DoS by requiring all clients

Re: [Bitcoin-development] Proposal: PoW-based throttling of addresses (was: Outbound connections rotation)

2014-11-13 Thread Isidor Zeuner
Hi Mike, hi Ivan, hi all, Since when? This has been a recognized approach since people called it hashcash ([1] - before cryptocurrencies were even invented). I only know of one site that worked the way you propose: TicketMaster, a long time ago. They used it as a less harsh form of

Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P network paper

2014-11-26 Thread Isidor Zeuner
Hello there, quote: Please see also the following: https://cpunks.org//pipermail/cypherpunks/2014-November/005971.html I agree about the severity of the Tor/Bitcoin issue, but I see no point in bashing Bitcoin's financial privacy characteristics as the linked pages seem to do. Bitcoin can

Re: [Bitcoin-development] Proposal: PoW-based throttling of addresses (was: Outbound connections rotation)

2014-11-26 Thread Isidor Zeuner
Hi Mike, thanks for your assessment. Please find my replies in-line: DKIM is hardly a PoW; signing is cheap and gets cheaper all the time. I used to work in the email business and big bulk mailers all spent far more CPU time on other aspects of their business, the overhead of DKIM is

Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P network paper

2014-12-01 Thread Isidor Zeuner
Hi Gregory, response below quote: Since this attack vector has been discussed, I started making some measurements on how effective it is to connect to Bitcoin using Tor, and I found that the number of connections dropping to near-zero is a situation which occurs rather frequently, which

Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P network paper

2014-12-08 Thread Isidor Zeuner
[As an aside I agree that there are lots of things to improve here, but the fact that users can in theory be forced off of tor via DOS attacks is not immediately concerning to me because its a conscious choice users would make to abandon their privacy Bitcoin already has a large

Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P network paper

2014-12-11 Thread Isidor Zeuner
[...] And, on the flip side if the host is persistently behind tor, even with some watermarkable behaviour, their privacy is protected. So making sure that hosts can continually use tor (or similar systems) should be the higher priority. (And, of course, not reimplementing tor leverages

Re: [Bitcoin-development] Merged mining a side chain with proof of burn on parent chain

2014-12-11 Thread Isidor Zeuner
[...] The Bitcoin miner will include burn transactions because they offer Bitcoin fees. Bitcoin miner can not selectively block side chains since the hashes associated with the burn do not disclose which side chain or other project they are for. Here you have a “merged mining” that does not

Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P network paper

2014-12-15 Thread Isidor Zeuner
[...] I'm confused by this, I run quite a few nodes exclusively on tor and chart their connectivity and have seen no such connection dropping behaviour. In my experience the problem has always been getting bootstrapped. Most nodes hardly give any hidden service nodes in their getaddr.

Re: [Bitcoin-development] Merged mining a side chain with proof of burn on parent chain

2014-12-15 Thread Isidor Zeuner
The goal is to have an opportunity cost to breaking the rules. Proof of Burn is a real cost for following the rules. For every participant who could try to decide about the adequateness of the cost, no direct effect comes from the difference between Proof of Burn, and approaches which keep

[Bitcoin-development] determining change addresses using the least significant digits

2015-02-04 Thread Isidor Zeuner
Hi there, traditionally, the Bitcoin client strives to hide which output addresses are change addresses going back to the payer. However, especially with today's dynamically calculated miner fees, this may often be ineffective: A user sending a payment using the Bitcoin client will usually enter

Re: [Bitcoin-development] Merged mining a side chain with proof of burn on parent chain

2015-02-04 Thread Isidor Zeuner
Hi there, comments in-line: I later wrote up the idea in the context of adding Zerocoin to Bitcoin: http://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg02472.html For the sake of maximum clarity with respect to modelling the value of a Bitcoin, I don't think that

Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P network paper

2015-01-21 Thread Isidor Zeuner
Hi there, some thoughts in-line: Finally, distributors of consumer wallets can use this research in order to distribute their wallet with policies which may be less prone to Tor-specific attacks. Or leave this out altogether if their audience has different expectations for connecting to

Re: [Bitcoin-development] BIP70: why Google Protocol Buffers for encoding?

2015-01-24 Thread Isidor Zeuner
For what it's worth, there was consideration of replacing protocol buffers when modifying BIP70 to function with the altcoin I work on (changes were required anyway in eliminate any risk that payment requests could not be accidentally applied to the wrong blockchain). Why not serialize some

Re: [Bitcoin-development] BIP70: why Google Protocol Buffers for encoding?

2015-03-14 Thread Isidor Zeuner
That was essentially what we did in the end, we replaced the network identifier (main/test) with the genesis block hash. The result is never going to accidentally work with Bitcoin Core (nor vice-versa), but is readily extensible to any other altcoins that want to use the specification