In this paper, we introduce a new notion that we call Non-Atomic Payment Splitting (NAPS) protocols that allow the intermediaries in the network to split the payments recursively into several subpayments in such a way that the payment can be successful ``partially'' (i.e.~not all the requested amount may be transferred). This is in contrast with the existing splitting techniques that are ``atomic'' in the sense that they did not allow such partial payments (we compare the ``atomic'' and ``non-atomic'' approaches in the paper). We define NAPS formally and then present a protocol that we call ``EthNA'', that satisfies this definition. EthNA is based on very simple and efficient cryptographic tools, and in particular, it does not use any expensive cryptographic primitives. We implement a simple variant of \EthNA in Solidity and provide some benchmarks. We also report on some experiments with routing using \Ethna.
Category / Keywords: cryptographic protocols / blockchain, smart contracts, payment networks Date: received 12 Feb 2020, last revised 20 Nov 2021 Contact author: stefan dziembowski at crypto edu pl, pk332217 at students mimuw edu pl Available format(s): PDF | BibTeX Citation Note: major revision (including title change) Version: 20211120:114142 (All versions of this report) Short URL: ia.cr/2020/166