Chameleon Hash Time-Lock Contract for privacy preserving payment channel networks

Bin Yu, Shabnam Kasra Kermanshahi, Amin Sakzad, Surya Nepal

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

17 Citations (Scopus)


Payment channel networks (PCNs) have been proposed to address the low transaction throughput of the permissionless blockchain protocols. Though the PCNs allow users to have the unlimited number of transactions in the channel without interacting with blockchain, it leaks the entire payment paths to the public. To address the payment path leakage issue, we propose a Chameleon-hash based payment protocol, called Chameleon Hash Time-Lock Contract (CHTLC). Using Chameleon-hash function in a multi-layer fashion guarantees that no user can recover the payment path if at least one intermediate payment node is honest. For the same payment path, compared with Multi-hop Hash Time-Lock Contract (MHTLC) protocol of Malavolta et al. [1], CHTLC is 5 times faster in the payment data initialisation, and the communication bandwidth is reduced significantly from 17, 000 KB to just 7.7 KB.

Original languageEnglish
Title of host publicationProvable Security
Subtitle of host publication13th International Conference, ProvSec 2019 Cairns, QLD, Australia, October 1–4, 2019 Proceedings
EditorsRon Steinfeld, Tsz Hon Yuen
Place of PublicationCham Switzerland
Number of pages16
ISBN (Electronic)9783030319199
ISBN (Print)9783030319182
Publication statusPublished - 2019
EventInternational Conference on Provable Security 2019 - Cairns, Australia
Duration: 1 Oct 20194 Oct 2019
Conference number: 13th (Proceedings)

Publication series

NameLecture Notes in Computer Science
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


ConferenceInternational Conference on Provable Security 2019
Abbreviated titleProvSec 2019
Internet address


  • Blockchain
  • Payment channel networks
  • Payment privacy

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