The Bitcoin scalability problem has led to the development of offchain
financial mechanisms such as payment channel networks
(PCNs) which help users process transactions of varying amounts,
including micro-payment transactions, without writing each transaction
to the blockchain. Since PCNs only allow path-based transactions,
effective, secure routing protocols that find a path between
a sender and receiver are fundamental to PCN operations. In this
paper, we propose RACED, a routing protocol that leverages the
idea of Distributed Hash Tables (DHTs) to route transactions in
PCNs in a fast and secure way. Our experiments on real-world
transaction datasets show that RACED gives an average transaction
success ratio of 98.74%, an average pathfinding time of 31.242
seconds, which is 1.65 × 103, 1.8 × 103, and 4 × 102 times faster
than three other recent routing protocols that offer comparable
security/privacy properties. We rigorously analyze and prove the
security of RACED in the Universal Composability framework.
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This content will become publicly available on July 1, 2025
SPRITE: Secure and Private Routing in Payment Channel Networks
Payment channel networks are a promising solution to the scalability
challenge of blockchains and are designed for significantly increased
transaction throughput compared to the layer one blockchain.
Since payment channel networks are essentially decentralized peerto-
peer networks, routing transactions is a fundamental challenge.
Payment channel networks have some unique security and privacy
requirements that make pathfinding challenging, for instance, network
topology is not publicly known, and sender/receiver privacy
should be preserved, in addition to providing atomicity guarantees
for payments. In this paper, we present an efficient privacypreserving
routing protocol, SPRITE, for payment channel networks
that supports concurrent transactions. By finding paths offline
and processing transactions online, SPRITE can process transactions
in just two rounds, which is more efficient compared to
prior work. We evaluate SPRITE’s performance using Lightning
Network data and prove its security using the Universal Composability
framework. In contrast to the current cutting-edge methods
that achieve rapid transactions, our approach significantly reduces
the message complexity of the system by 3 orders of magnitude
while maintaining similar latencies.
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- Award ID(s):
- 2148358
- NSF-PAR ID:
- 10502897
- Publisher / Repository:
- ACM Asia Conference on Computer and Communications Security (ACM AsiaCCS)
- Date Published:
- Journal Name:
- ACM Asia Conference on Computer and Communications Security (ACM AsiaCCS)
- Subject(s) / Keyword(s):
- Privacy preserving protocols, Payment channel networks, Secure pathfinding
- Format(s):
- Medium: X
- Location:
- Singapore
- Sponsoring Org:
- National Science Foundation
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