# Online Payment Network Design

## TL;DR

This paper investigates the problem of designing online payment networks with a central coordinator to maximize accepted transactions under capital constraints, revealing fundamental limitations through various impossibility results.

## Contribution

It introduces the online network design problem for payment channels and provides new impossibility results for both deterministic and randomized algorithms.

## Key findings

- Impossibility results for deterministic algorithms against adaptive adversaries
- Impossibility results for randomized algorithms against oblivious adversaries
- Insights into the limitations of online payment network design

## Abstract

Payment channels allow transactions between participants of the blockchain to be executed securely off-chain, and thus provide a promising solution for the scalability problem of popular blockchains. We study the online network design problem for payment channels, assuming a central coordinator. We focus on a single channel, where the coordinator desires to maximize the number of accepted transactions under given capital constraints. Despite the simplicity of the problem, we present a flurry of impossibility results, both for deterministic and randomized algorithms against adaptive as well as oblivious adversaries.