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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Verifying vMVCC, a high-performance transaction library using multi-version concurrency control
Multi-version concurrency control (MVCC) is a widely used, sophisticated approach for handling concurrent transactions. vMVCC is the first MVCC-based transaction library that comes with a machine-checked proof of correctness, providing clients with a guarantee that it will correctly handle all transactions despite a complicated design and implementation that might otherwise be error-prone. vMVCC is implemented in Go, stores data in memory, and uses several optimizations, such as RDTSC-based timestamps, to achieve high performance (25–96% the throughput of Silo, a state-of-the-art in-memory database, for YCSB and TPC-C workloads). Formally specifying and verifying vMVCC required adopting advanced proof techniques, such as logical atomicity and prophecy variables, owing to the fact that MVCC transactions can linearize at timestamp generation prior to transaction execution.
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- Award ID(s):
- 2123864
- NSF-PAR ID:
- 10438568
- Date Published:
- Journal Name:
- Proceedings of the 17th USENIX Symposium on Operating Systems Design and Implementation (OSDI)
- Page Range / eLocation ID:
- 871-886
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- The DOI is not currently available.
