https://xuezcoin.com/ XUEZ is a community-based project, aiming to address the inherent problems plaguing Bitcoin and other cryptocurrencies. Understanding the importance of anonymity as well as usability, XUEZ provides a 8MB block size that results in close to instantaneous transaction times.
arXiv:1605.07524 Date: submitted by
2017-03-24 Author(s): Maria Apostolaki
, Aviv Zohar
, Laurent Vanbever
As the most successful cryptocurrency to date, Bitcoin constitutes a target of choice for attackers. While many attack vectors have already been uncovered, one important vector has been left out though: attacking the currency via the Internet routing infrastructure itself. Indeed, by manipulating routing advertisements (BGP hijacks) or by naturally intercepting traffic, Autonomous Systems (ASes) can intercept and manipulate a large fraction of Bitcoin traffic. This paper presents the first taxonomy of routing attacks and their impact on Bitcoin, considering both small-scale attacks, targeting individual nodes, and large-scale attacks, targeting the network as a whole. While challenging, we show that two key properties make routing attacks practical: (i) the efficiency of routing manipulation; and (ii) the significant centralization of Bitcoin in terms of mining and routing. Specifically, we find that any network attacker can hijack few (<100) BGP prefixes to isolate ~50% of the mining power---even when considering that mining pools are heavily multi-homed. We also show that on-path network attackers can considerably slow down block propagation by interfering with few key Bitcoin messages. We demonstrate the feasibility of each attack against the deployed Bitcoin software. We also quantify their effectiveness on the current Bitcoin topology using data collected from a Bitcoin supernode combined with BGP routing data. The potential damage to Bitcoin is worrying. By isolating parts of the network or delaying block propagation, attackers can cause a significant amount of mining power to be wasted, leading to revenue losses and enabling a wide range of exploits such as double spending. To prevent such effects in practice, we provide both short and long-term countermeasures, some of which can be deployed immediately.
 “A Next-Generation Smart Contract and Decentralized Application Platform ,” https://github.com/ethereum/wiki/wiki/White-Paper
 “Bitcoin Blockchain Statistics,” https://blockchain.info/
 “bitnodes,” https://bitnodes.21.co/
 “Bitnodes. Estimating the size of Bitcoin network,” https://bitnodes.21.co/
 “CAIDA Macroscopic Internet Topology Data Kit.” https://www.caida.org/data/internet-topology-data-kit/
 “Dyn Research. Pakistan hijacks YouTube.” http://research.dyn.com/2008/02/pakistan-hijacks-youtube-1/
 “FALCON,” http://www.falcon-net.org/
 “FIBRE,” http://bitcoinfibre.org/
 “Litecoin ,” https://litecoin.org
 “RIPE RIS Raw Data,” https://www.ripe.net/data-tools/stats/ris/ris-raw-data
 “Routeviews Prefix to AS mappings Dataset (pfx2as) for IPv4 and IPv6.” https://www.caida.org/data/routing/routeviews-prefix2as.xml
 “Scapy.” http://www.secdev.org/projects/scapy/
 “The Relay Network,” http://bitcoinrelaynetwork.org/
 “ZCash,” https://z.cash/
 A. M. Antonopoulos, “The bitcoin network,” in Mastering Bitcoin. O’Reilly Media, Inc., 2013, ch. 6.
 H. Ballani, P. Francis, and X. Zhang, “A Study of Prefix Hijacking and Interception in the Internet,” ser. SIGCOMM ’07. New York, NY, USA: ACM, 2007, pp. 265–276.
 A. Boldyreva and R. Lychev, “Provable Security of S-BGP and Other Path Vector Protocols: Model, Analysis and Extensions,” ser. CCS ’12. New York, NY, USA: ACM, 2012, pp. 541–552.
 J. Bonneau, A. Miller, J. Clark, A. Narayanan, J. A. Kroll, and E. W. Felten, “Sok: Research perspectives and challenges for bitcoin and cryptocurrencies,” in Security and Privacy (SP), 2015 IEEE Symposium on. IEEE, 2015, pp. 104–121.
 P. Bosshart, D. Daly, G. Gibb, M. Izzard, N. McKeown, J. Rexford, C. Schlesinger, D. Talayco, A. Vahdat, G. Varghese et al., “P4: Programming protocol-independent packet processors,” ACM SIGCOMM Computer Communication Review, vol. 44, no. 3, pp. 87–95, 2014.
 C. Decker and R. Wattenhofer, “Information propagation in the bitcoin network,” in Peer-to-Peer Computing (P2P), 2013 IEEE Thirteenth International Conference on. IEEE, 2013, pp. 1–10.
 ——, Bitcoin Transaction Malleability and MtGox. Cham: Springer International Publishing, 2014, pp. 313–326. [Online]. Available: http://dx.doi.org/10.1007/978-3-319-11212-1_18
 M. Edman and P. Syverson, “As-awareness in tor path selection,” in Proceedings of the 16th ACM Conference on Computer and Communications Security, ser. CCS ’09, 2009.
 I. Eyal, “The miner’s dilemma,” in 2015 IEEE Symposium on Security and Privacy. IEEE, 2015, pp. 89–103.
 I. Eyal and E. G. Sirer, “Majority is not enough: Bitcoin mining is vulnerable,” in Financial Cryptography and Data Security. Springer, 2014, pp. 436–454.
 N. Feamster and R. Dingledine, “Location diversity in anonymity networks,” in WPES, Washington, DC, USA, October 2004.
 J. Garay, A. Kiayias, and N. Leonardos, “The bitcoin backbone protocol: Analysis and applications,” in Advances in Cryptology-EUROCRYPT 2015. Springer, 2015, pp. 281–310.
 A. Gervais, G. O. Karama, V. Capkun, and S. Capkun, “Is bitcoin a decentralized currency?” IEEE security & privacy, vol. 12, no. 3, pp. 54–60, 2014.
 A. Gervais, H. Ritzdorf, G. O. Karame, and S. Capkun, “Tampering with the delivery of blocks and transactions in bitcoin,” in Proceedings of the 22Nd ACM SIGSAC Conference on Computer and Communications Security, ser. CCS ’15. New York, NY, USA: ACM, 2015, pp. 692–705.
 P. Gill, M. Schapira, and S. Goldberg, “Let the Market Drive Deployment: A Strategy for Transitioning to BGP Security,” ser. SIGCOMM ’11. New York, NY, USA: ACM, 2011, pp. 14–25.
 S. Goldberg, M. Schapira, P. Hummon, and J. Rexford, “How Secure Are Secure Interdomain Routing Protocols,” in SIGCOMM, 2010.
 E. Heilman, A. Kendler, A. Zohar, and S. Goldberg, “Eclipse attacks on bitcoin’s peer-to-peer network,” in 24th USENIX Security Symposium (USENIX Security 15), 2015, pp. 129–144.
 Y.-C. Hu, A. Perrig, and M. Sirbu, “SPV: Secure Path Vector Routing for Securing BGP,” ser. SIGCOMM ’04. New York, NY, USA: ACM, 2004, pp. 179–192.
 J. Karlin, S. Forrest, and J. Rexford, “Pretty Good BGP: Improving BGP by Cautiously Adopting Routes,” in Proceedings of the Proceedings of the 2006 IEEE International Conference on Network Protocols, ser. ICNP ’06. Washington, DC, USA: IEEE Computer Society, 2006, pp. 290–299.
 E. K. Kogias, P. Jovanovic, N. Gailly, I. Khoffi, L. Gasser, and B. Ford, “Enhancing bitcoin security and performance with strong consistency via collective signing,” in 25th USENIX Security Symposium (USENIX Security 16). Austin, TX: USENIX Association, 2016, pp. 279–296.
 J. A. Kroll, I. C. Davey, and E. W. Felten, “The economics of bitcoin mining, or bitcoin in the presence of adversaries.” Citeseer.
 A. Miller, J. Litton, A. Pachulski, N. Gupta, D. Levin, N. Spring, and B. Bhattacharjee, “Discovering bitcoin’s public topology and influential nodes.”
 S. J. Murdoch and P. Zielinski, “Sampled traffic analysis by Internet- ´ exchange-level adversaries,” in Privacy Enhancing Technologies: 7th International Symposium, PET 2007, N. Borisov and P. Golle, Eds. Springer-Verlag, LNCS 4776, 2007, pp. 167–183.
 K. Nayak, S. Kumar, A. Miller, and E. Shi, “Stubborn mining: Generalizing selfish mining and combining with an eclipse attack,” IACR Cryptology ePrint Archive, vol. 2015, p. 796, 2015.
 T. Neudecker, P. Andelfinger, and H. Hartenstein, “A simulation model for analysis of attacks on the bitcoin peer-to-peer network,” in IFIP/IEEE International Symposium on Internet Management. IEEE, 2015, pp. 1327–1332.
 P. v. Oorschot, T. Wan, and E. Kranakis, “On interdomain routing security and pretty secure bgp (psbgp),” ACM Trans. Inf. Syst. Secur., vol. 10, no. 3, Jul. 2007.
 A. Pilosov and T. Kapela, “Stealing The Internet. An Internet-Scale Man In The Middle Attack.” DEFCON 16.
 Y. Rekhter and T. Li, A Border Gateway Protocol 4 (BGP-4), IETF, Mar. 1995, rFC 1771.
 M. Rosenfeld, “Analysis of hashrate-based double spending,” arXiv preprint arXiv:1402.2009, 2014.
 A. Sapirshtein, Y. Sompolinsky, and A. Zohar, “Optimal selfish mining strategies in bitcoin,” CoRR, vol. abs/1507.06183, 2015.
 E. B. Sasson, A. Chiesa, C. Garman, M. Green, I. Miers, E. Tromer, and M. Virza, “Zerocash: Decentralized anonymous payments from bitcoin,” in 2014 IEEE Symposium on Security and Privacy. IEEE, 2014, pp. 459–474.
 B. Schlinker, K. Zarifis, I. Cunha, N. Feamster, and E. Katz-Bassett, “Peering: An as for us,” in Proceedings of the 13th ACM Workshop on Hot Topics in Networks, ser. HotNets-XIII. New York, NY, USA: ACM, 2014, pp. 18:1–18:7.
 J. Schnelli, “BIP 151: Peer-to-Peer Communication Encryption,” Mar. 2016, https://github.com/bitcoin/bips/blob/mastebip-0151.mediawiki
 X. Shi, Y. Xiang, Z. Wang, X. Yin, and J. Wu, “Detecting prefix hijackings in the Internet with Argus,” ser. IMC ’12. New York, NY, USA: ACM, 2012, pp. 15–28.
 Y. Sompolinsky and A. Zohar, “Secure high-rate transaction processing in bitcoin,” in Financial Cryptography and Data Security. Springer, 2015, pp. 507–527.
 Y. Sun, A. Edmundson, L. Vanbever, O. Li, J. Rexford, M. Chiang, and P. Mittal, “RAPTOR: Routing attacks on privacy in TOR.” in USENIX Security, 2015.
 A. Tonk, “Large scale BGP hijack out of India,” 2015, http://www.bgpmon.net/large-scale-bgp-hijack-out-of-india/
 ——, “Massive route leak causes Internet slowdown,” 2015, http://www.bgpmon.net/massive-route-leak-cause-internet-slowdown/
 L. Vanbever, O. Li, J. Rexford, and P. Mittal, “Anonymity on quicksand: Using BGP to compromise TOR,” in ACM HotNets, 2014.
 Z. Zhang, Y. Zhang, Y. C. Hu, and Z. M. Mao, “Practical defenses against BGP prefix hijacking,” ser. CoNEXT ’07. New York, NY, USA: ACM, 2007.
 Z. Zhang, Y. Zhang, Y. C. Hu, Z. M. Mao, and R. Bush, “iSPY: Detecting IP prefix hijacking on my own,” IEEE/ACM Trans. Netw., vol. 18, no. 6, pp. 1815–1828, Dec. 2010.
I've posted this before and was criticized because it was claimed this was a future problem. Actually, the block reward goes pretty low pretty fast. Already 80% of coins are already mined. This is a future problem, but guess what? So are cores hypothetical centralization problems that are supremely trumped by this problem. submitted by
Cores hypothetical in the future problem is that miners will geographically centralize because the latency of relaying large blocks will result in close miners having an advantage. The relay network which allows blocks to transmit without latency issues shouldn't count according to core because it is not "decentralized".
The other part of their "decentralization" argument is that we need to all run full nodes to make transactions, but then fail to give an example of anyone being defrauded by an SPV wallet. They then give statistics for how full nodes are dropping (without factoring in that the original bitcoin wallets were all full nodes which skews the statistics)
While network hashrate of BTC (8000 PH/s currently) about 10k of ETH (0.105 PH/s) and while you will spend about 4400000 GH/s to generate one BTC in a day, compared to 88 GH/s to generate 13.5ETH the equivalent of one BTC per day, submitted by
Is it safe to say we will need to multiply ETH network hashrate by 50000 (the equivalent of 4400000/88) to be able to compare it with BTC network (size) hashpower? in another word, if BTC network size in hashing power is 8000 PH/s then ETH network size using hashing power to compare should be 0.105 PH/s * 50000 = 5250! which means the Ethereum network size is 65.6% of Bitcoin network size?
Bitcoin Cash is a Bitcoin hard fork that raises the Bitcoin (Cash) block size to 32MB, allowing the BCH network to process around 65 transactions per second. The Bitcoin Cash hard fork took place in August 2017, just before the conclusion of the SegWit and SegWit2x debacle. In many ways, the Bitcoin Cash movement and hard fork was a result of the lack of direction by the latter project. This page displays the number and size of the unconfirmed bitcoin transactions, also known as the transactions in the mempool. It gives a real-time view and shows how the mempool evolves over the time. The transactions are colored by the amount of fee they pay per (virtual) byte. The data is generated from my full node and is updated every minute. Note that in bitcoin there is no global ... The total size of the blockchain minus database indexes in megabytes. Products. Wallet Buy ... Network Activity. Wallet Activity. Market Signals. Sponsored Content. Blockchain Size (MB) The total size of the blockchain minus database indexes in megabytes. 30 Days 60 Days 180 Days 1 Year 3 Years All Time. Raw Values 7 Day Average 30 Day Average. Linear Scale Logarithmic Scale. You’ve thought ... Weight units are a measurement used to compare the size of different Bitcoin transactions to each other in proportion to the consensus-enforced maximum block size limit.Weight units are also used to measure the size of other block chain data, such as block headers.As of Bitcoin Core 0.13.0 (released August 2016), each weight unit represents 1/4,000,000th of the maximum size of a block. The size of the Bitcoin blockchain has experienced consistently high levels of growth since its creation, reaching approximately 285.06 gigabytes in size as of the end of June 2020.
Support the Channel via BTC Lightning Network: https://tippin.me/@ ... Watch in 360 the inside of a nuclear reactor from the size of an atom with virtual reality - Duration: 3:42. EDF in the UK ... Biccoin Core, with its off-chain Segwit and Lightning Network solutions protect smaller miners by limiting the size of the blocks each miner can mine. Bitcoin Unlimited urge miners to grow as ... In this episode for Lightning Month, I talk with Tadge Dryja, the co-author of the Lightning Network whitepaper. We discuss the limitations of the lightning network, why Bitcoin might not be for ... See if you could imagine the amount of Gigs it takes from your HD. This is the first video in a series on working with the bitcoin lightning network, a second layer trustless network on top of bitcoin. In this video I go over the initial setup process which will ...