Public blockchains inherently offer low throughput and high latency, motivating off-chain scalability solutions such as Payment Channel Networks (PCNs). However, existing PCNs suffer from liquidity fragmentation-funds locked in one channel cannot be reused elsewhere-and channel depletion, both of which limit routing efficiency and reduce transaction success rates. Multi-party channel (MPC) constructions mitigate these issues, but they typically rely on leaders or coordinators, creating single points of failure and providing only limited flexibility for inter-channel payments. We introduce Hypergraph-based Multi-Party Payment Channels (COALESCE), a new off-chain construction that replaces bilateral channels with collectively funded hyperedges. These hyperedges enable fully concurrent, leaderless intra- and inter-hyperedge payments through verifiable, proposer-ordered DAG updates, offering significantly greater flexibility and concurrency than prior designs. Hence our, design eliminates routing dependencies, avoids directional liquidity lock-up, and does not require central monitoring services such as watchtowers. Our implementation on a 150-node intra-hyperedge achieves a transaction success rate of approximately 94% under heavy load (larger payment sizes), while full hyperedge evaluation over a 15,000-node network sustains success rates in the range of 85% to 95%, without HTLC expiry or routing failures, highlighting the robustness of COALESCE.

翻译：公共区块链天然具有低吞吐量和高延迟的特性，这推动了支付通道网络（PCN）等链下扩容解决方案的发展。然而，现有PCN面临流动性碎片化问题——锁定在一个通道中的资金无法在其他地方重复使用，以及通道耗尽问题，这两者都限制了路由效率并降低了交易成功率。多方通道（MPC）构造在一定程度上缓解了这些问题，但它们通常依赖领导者或协调者，从而造成单点故障，并且为通道间支付提供的灵活性有限。我们提出了基于超图的多方支付通道（COALESCE），这是一种新的链下构造，用集体资助的超边替代了双边通道。这些超边通过可验证的、提议者排序的有向无环图（DAG）更新，实现了完全并发、无领导者的超边内及超边间支付，比以往的设计提供了显著更强的灵活性和并发性。因此，我们的设计消除了路由依赖，避免了定向流动性锁定，并且不需要诸如瞭望塔之类的中心监控服务。我们在一个包含150个节点的超边内实现，在高负载（大额支付）下实现了约94%的交易成功率；而在一个包含15,000个节点的网络上进行的全面超边评估，成功率保持在85%至95%的范围内，且未出现HTLC过期或路由失败，突显了COALESCE的鲁棒性。