On the Difficulty of Hiding the Balance of Lightning Network Channels
On the Difficulty of Hiding the Balance of Lightning Network Channels
复制标题
论闪电网络通道平衡隐藏之难
DOI：
10.1145/3321705.3329812
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Joaquín García
中科院分区：
文献类型：
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作者：
J. Herrera;G. Navarro;Alejandro Ranchal;Cristina Pérez;Joaquín García
闪电网络是运行在比特币和其他区块链之上的第二层技术。它由一个点对点网络组成，用于传输原始信息数据。点对点网络中的一些链接被识别为支付通道，用于在两个闪电网络客户端之间进行支付（即，信道的两个节点）。支付渠道都是用固定的信用额度建立起来的，渠道容量。信道容量与节点的IP地址一起被发布，以允许路由算法找到不具有直接支付信道的两个节点之间的现有路径。然而，为了保护用户的隐私，给定信道的节点对的精确平衡（即，信道在每个方向上的带宽）是保密的。由于余额没有公布，第二层节点迭代地探测路由，直到它们找到一个成功的路由到目的地所需的金额，如果有的话。此功能使路由发现协议效率较低，但保留了信道平衡的隐私。在本文中，我们提出了一种攻击，以揭示闪电网络中通道的平衡。我们的攻击是基于执行多个支付，确保没有一个是最终的，最大限度地减少攻击的经济成本。我们提出的实验结果，验证我们的主张，并采取对策来处理攻击。
The Lightning Network is a second layer technology running on top of Bitcoin and other Blockchains. It is composed of a peer-to-peer network, used to transfer raw information data. Some of the links in the peer-to-peer network are identified as payment channels, used to conduct payments between two Lightning Network clients (i.e., the two nodes of the channel). Payment channels are created with a fixed credit amount, the channel capacity. The channel capacity, together with the IP address of the nodes, is published to allow a routing algorithm to find an existing path between two nodes that do not have a direct payment channel. However, to preserve users' privacy, the precise balance of the pair of nodes of a given channel (i.e. the bandwidth of the channel in each direction), is kept secret. Since balances are not announced, second-layer nodes probe routes iteratively, until they find a successful route to the destination for the amount required, if any. This feature makes the routing discovery protocol less efficient but preserves the privacy of channel balances. In this paper, we present an attack to disclose the balance of a channel in the Lightning Network. Our attack is based on performing multiple payments ensuring that none of them is finalized, minimizing the economical cost of the attack. We present experimental results that validate our claims, and countermeasures to handle the attack.