# Map-Z: Exposing the Zcash Network in Times of Transition

## TL;DR

This paper presents the first long-term measurement study of the Zcash network, revealing key metrics and node interconnections, and introduces an inference method adaptable to other cryptocurrencies for topology analysis.

## Contribution

It provides the first comprehensive analysis of Zcash's network structure and proposes a novel timing-based inference method for uncovering node interconnections.

## Key findings

- Achieved 50% precision and 82% recall in real-world topology inference.
- Revealed insights into Zcash network size, node distribution, and centralization.
- Demonstrated the adaptability of the inference method to other cryptocurrencies.

## Abstract

Zcash is a privacy-preserving cryptocurrency that provides anonymous monetary transactions. While Zcash's anonymity is part of a rigorous scientific discussion, information on the underlying peer-to-peer network are missing. In this paper, we provide the first long-term measurement study of the Zcash network to capture key metrics such as the network size and node distribution as well as deeper insights on the centralization of the network. Furthermore, we present an inference method based on a timing analysis of block arrivals that we use to determine interconnections of nodes. We evaluate and verify our method through simulations and real-world experiments, yielding a precision of 50 % with a recall of 82 % in the real-world scenario. By adjusting the parameters, the topology inference model is adaptable to the conditions found in other cryptocurrencies and therefore also contributes to the broader discussion of topology hiding in general.