Conference Paper

Locality Based Approach to Improve Propagation Delay on the Bitcoin Peer-to-Peer Network

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Abstract

Scalability in Bitcoin, a peer-to-peer electronic currency system, is a complicated issue which prevents the Bitcoin from gaining increasing popularity nowadays. In this paper, we propose a new approach, that is based on how the clusters are formulated and the nodes define their membership, to improve the transaction propagation delay in the Bitcoin network. In this approach, the locality of connectivity in the Bitcoin network is increased by grouping Bitcoin nodes based on their geographical location. Our simulations show that location based-distance better defines clustering structures that optimize the performance of the transaction propagation delay. A key reason for this improvement is mainly due to the reduction of the communication link cost measured by the distance between nodes. Compared to the existing clustering protocol (BCBSN) that we proposed in our previous work, location based clustering is more effective at reducing the transaction propagation delay.

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... According to this trouble which related with the trouble of getting a unanimity on a web of Bitcoin, it categorized by way of an aspect of the Byzantine mistake leniency that wants for remaining a framework active in any case for Byzantine impairment. A possibility for getting the Byzantine unanimity at the concurrent framework in any case for many of incorrect entrants that demonstrated by [7]. Beneath a roof for Bitcoin, it found that excluding to the fiddling possibility while Byzantine misconception makes up minus more half a web, the Bitcoin procedure able to get the unanimity [8], [9]. ...
... They also discovered some of the security holes that the feather coin had experienced and could repair these gaps and also raised the protection level in that currency. By doing this step, you will have taken a crucial step toward creating your own digital currency that is strong and flexible as well as protection [4][5][6][7]. ...
... Most of those who copied the source code of the currency Bitcoin or Laitcoin and reused without changing it, their currencies could not succeed and continue their currency failed. So you should not only get the source code for one of the two currencies in this step without changing it, but you must change and modify it and insert some features and features to ensure the continuity and success of your digital currency [4][5][6][7]. ...
... Among these rules, 'Rule 1' is the default behavior of Bitcoin clients, and 'Rule 5' is our proposed approach where we have used x=3, y=3, and z=2. Rules 2∼4 are implemented for comparison purposes, where Rules 2 and 3 may be considered similar to what was proposed by Fadhil et al. [21], [24]. However, their work either had an unclear notion of 'long' link, or had a strict cut-off threshold of 100km which would not work if there were no peers within 100km or outside 100km. ...
... Figure 13 is the CDF of the same result in Figure 12. It shows more clearly that 'Near-Mid-Far' approach improves on the latency distribution of information propagation, and confirms that 'Nearest' or 'Clustering' ( [21], [24]) approaches should not be selected. The reason for such result can be inferred from Figure 14 which plots the CDF of the number of forwarding hops required (by recursive flooding) for information propagation to all nodes in the Bitcoin network using various peer selection rules. ...
... There are also a few prior work that attempts to tackle the problem of information propagation delay in the Bitcoin network [7], [21], [24], one of which we have already mentioned above (Decker et al. [7]) ...
Article
Bitcoin is a decentralized digital currency that has gained significant attention and growth in recent years. Unlike traditional currencies, Bitcoin does not rely on a centralized authority to control the supply, distribution, and verification of the validity of transactions. Instead, Bitcoin relies on a peer-topeer network of volunteers to distribute pending transactions and confirmed blocks, verify transactions, and to collectively implement a replicated ledger that everyone agrees on. This peer-to-peer (P2P) network is at the heart of Bitcoin and many other blockchain technologies. In this article, we present a comparative measurement study of nodes in the Bitcoin network. We measure and analyze how many so-called ‘volunteers’ are in Bitcoin P2P network by scanning the live Bitcoin network for 37 days in 2018, and compare them with data reported by prior work in 2013~2016. Our work is motivated by the fact that Bitcoin has experienced explosive growth in terms of number of users, transactions, value, and interest over the recent couple years. Our investigation includes the IP addresses of Bitcoin nodes, size of the network, power-law in the geographic distribution, protocol and client versions, and network latencies, and show how today’s network is different from early days. In addition, based on the observations made from the measurement study, we propose a simple distance-based peer selection rule for improved connectivity and faster data propagation. Evaluation results show that our proposed light-weight and backward-compatible peer selection rule has potential to reduce data dissemination latency.
... It adapts a cryptographic proof of work (PoW) mechanism that allows anonymous peers to create and validate transactions through the underlying peer-to-peer (P2P) network [4]. The P2P network is vital to the communications of the blockchain system [12] [26]. The nodes send and receive messages via the underlying network infrastructure while the P2P topology is formed at the application layer [9]. ...
... This P2P topology is responsible for broadcasting new updates to peers by which they learn and inform each other about transactions and blocks [26]. The reachability of these messages affects the ability of the system to process more transactions and secure the interactions [12] [26]. ...
... Muntadher et al. [12] proposed locality-based approaches to improve the propagation delay on the P2P network. This study considered clustering nodes in the exact geographical location, where the distance between is used as key on choosing which nodes to add as a peer. ...
Preprint
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Bitcoin is the first and the most extensive decentralized electronic cryptocurrency system that uses blockchain technology. It uses a peer-to-peer (P2P) network to operate without a central authority and propagate system information such as transactions or blockchain updates. The communication between participating nodes is highly relying on the underlying network infrastructure to facilitate a platform. Understanding the impact of peer formation strategies, peer list, and delay are vital on understanding node to node communication. To this aim, we performed an extensive study on the transaction characteristic of Bitcoin through a Testbed. The analysis shows that peer selection strategies affect the transactions propagation and confirmation time. Moreover, the default distance-based peer selection strategy in Bitcoin performs less when there is high arrival intensity and creates high number forks.
... Propagation delays are influenced by the number of hops between nodes due to sparse peering, and the time required by software clients to verify and forward a block. Solutions have been proposed that cluster nodes to reduce latency [54], [26], but the authors note this may increase the potential for partitioning attacks. This indicates a trade-off between spatial and temporal vulnerability. ...
... The default number of Bitcoin peers is 8, which is used in our simulation. Studies have shown that peers are distributed, and can be associated with any AS [26]. Our experimental data confirmed this distribution. ...
... Discussion: Proposals were made to increase performance by favoring the establishing of connections to peers in geographic proximity [29]. Geographic proximity can be easily deducted using IP address information and freely available databases, hence, the required information can be easily obtained. ...
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Permissionless blockchains reach decentralized consensus without requiring pre-established identities or trusted third parties, thus enabling applications such as cryptocurrencies and smart contracts. Consensus is agreed on data that is generated by the application and transmitted by the system’s (peer-to-peer) network layer. While many attacks on the network layer were discussed so far, there is no systematic approach that brings together known attacks, the requirements, and the design space of the network layer. In this paper, we survey attacks on the network layer of permissionless blockchains, and derive five requirements: performance, low cost of participation, anonymity, DoS resistance, and topology hiding. Furthermore, we survey the design space of the network layer and qualitatively show the effect of each design decisions on the fulfillment of the requirements. Finally, we pick two aspects of the design space, in-band peer discovery and relay delay, and demonstrate possible directions of future research by quantitatively analyzing and optimizing simplified scenarios. We show that while most design decisions imply certain tradeoffs, there is a lack of models that analyze and formalize these tradeoffs. Such models could aid the design of the network layer of permissionless blockchains. One reason for the lack of models is the deliberately limited observability of deployed blockchains. We emphasize that simulation based approaches cope with these limitations and are suited for the analysis of the network layer of permissionless blockchains.
... In this paper the term bitcoin refers to the actual currency, while Bitcoin indicates the whole Bitcoin system. To function successfully, two main requirements need to be fulfilled: (i) transactions verification has to be performed in a distributed manner to ensure the validity of transactions, and (ii) successfully processed transactions have to be quickly announced to everyone to guarantee the state of the blockchain is consistent [4,5]. As transactions are validated against the blockchain, achieving a consistent state over the blockchain is a fundamental requirement for implementing a distributed transaction verification process. ...
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There is an increasing demand for digital crypto-currencies to be more secure and robust to meet the following business requirements: (1) low transaction fees and (2) the privacy of users. Nowadays, Bitcoin is gaining traction and wide adoption. Many well-known businesses have begun accepting bitcoins as a means of making financial payments. However, the susceptibility of Bitcoin networks to information propagation delay, increases the vulnerability to attack of the Bitcoin network, and decreases its throughput performance. This paper introduces and critically analyses new network clustering methods, named Locality Based Clustering (LBC), Ping Time Based Approach (PTBC), Super Node Based Clustering (SNBA), and Master Node Based Clustering (MNBC). The proposed methods aim to decrease the chances of performing a successful double spending attack by reducing the information propagation delay of Bitcoin. These methods embody proximity-aware extensions to the standard Bitcoin protocol, where proximity is measured geographically and in terms of latency. We validate our proposed methods through a set of simulation experiments and the findings show how the proposed methods run and their impact in optimising the transaction propagation delay. Furthermore, these new methods are evaluated from the perspective of the Bitcoin network's resistance to partitioning attacks. Numerical results, which are established via extensive simulation experiments, demonstrate how the extensions run and also their impact in optimising the transaction propagation delay. We draw on these findings to suggest promising future research directions for the optimisation of transaction propagation delays.
... This can reduce the unnecessary hops that the transaction passes through. Similarly, Location Based Clustering (LBC) protocol is proposed to increase the locality of connectivity in the Bitcoin network [15]. The communication link cost measured by the distance between nodes is significantly reduced using LBC. ...
Article
With the popularity of Bitcoin, there is a greater demand for the scalability of the Bitcoin blockchain, which is susceptible to the efficiency of block propagation. In the Bitcoin blockchain, efficient block propagation approach can reduce the computing power and the risk of forks. Meanwhile, larger blocks help to improve the throughput of transactions. Thus, the block propagation is a major issue of the scalability of the Bitcoin network. This paper introduces a method to reduce the required bandwidth of block propagation with erasure coding. To begin with, the network nodes are classified into several clusters. When a node wants to propagate a block, the node does not need to propagate the whole information of the block. Instead, the node can only transmit the transaction IDs and the coded information to each cluster. The simulation shows that the proposed method can significantly ease the network traffic among these clusters.
... However, there is still room for improving the optimal number of clusters by upgrading the network topology of the existing system. In another paper [18], the authors proposed an improvement of propagation time by grouping Bitcoin nodes according to the geographical location (location-based clustering). As a result, the location-based clustering model outperformed the predecessor protocol proposed in [17]. ...
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Propagation time on permissionless blockchain plays a significant role in terms of stability and performance in the decentralized systems. A large number of activities are disseminated to the whole nodes in the decentralized peer-to-peer network, thus causing propagation delay. The stability of the system is our concern in the first place. The propagation delay opens up opportunities for attackers to apply their protocol. Either by accelerating or decelerating the propagation time directly without proper calculation, it brings numerous negative impacts to the entire blockchain system. In this paper, we thoroughly review and elaborate on several parameters related to the propagation time in such a system. We describe our findings in terms of data communication, transaction propagation, and the possibility of an interference attack that caused an extra propagation time. Furthermore, we present the influence of block size, consensus, and blockchain scalability, including the relation of parameters. In the last session, we remark several points associated with the propagation time and use cases to avoid dilemmas in the light of the experiments and literary works.
... As the number of routing hops decreases, the propagation delay will also decrease. Subsequently in [2], the author evaluated the BCBSN protocol, which further proved its effectiveness in improving the block propagation speed. In [3], the author proposed a BCBPT protocol that clusters nodes based on the Ping delay between nodes to reduce the propagation delay of adjacent nodes in the network. ...
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At present, when the blockchain system propagates blocks, it is a point-to-point propagation of complete blocks. This method has three shortcomings: the propagation load is large; the message can only be received from one node; only after the complete block is received, can it be propagated to other nodes. Therefore, this article considers changing the block’s Merkel tree data structure to minimize the data size during block propagation while ensuring that the receiving node can reconstruct the correct and complete block. On the other hand, in order to be able to receive blocks from multiple nodes at the same time and relay to other nodes when incompletely received, the blocks are fragmented and then reorganized. At the same time, the correctness of a single fragment can also be verified.
... Although approaches already exist to optimize the propagation speed of information in the distributed ledger network [FOA16,FOA17], these also do not reach the performance of current financial transaction systems. In addition to optimizing the propagation speed, other improvements arise in the communication protocol used [GK17, CDE + 16]. ...
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... By clustering based on the locality of nodes, the propagation delay of transactions and blocks in the same cluster is reduced. The LBC (Location Based Clustering) protocol [19] and the BCBPT (Bitcoin Clustering Based on Ping Time) protocol [20] were further proposed. Nodes in the blockchain network were clustered according to physical location metrics such as their geographical location and Ping time to reduce the propagation delay of adjacent nodes. ...
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... In practice, blockchain-based systems have encountered scalability and performance issues (Eyal and Sirer, 2014;Atzei et al., 2017;Brandenburger et al., 2018). Thus, there have been proposals for performance improvements, which range from attempts at speeding up the blockchain overlay networks (e.g., (Corallo, 2016;Fadhil et al., 2017;Pinar Ozisik et al., 2017;Klarman et al., 2018;Basu et al., 2019;Coralo, 2019)) to proposals for increasing the throughput of the system (e.g., (Croman et al., 2016;Yu et al., 2018;Gueta et al., 2019;Yang et al., 2019)). While it is clear that these proposals are beneficial to the blockchain systems in terms of performance, it is not yet known what impact (positive or negative) they have on the other fundamental property of blockchain, which is network decentralization. ...
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