Understanding the "Airport" Censorship Circumvention Ecosystem in China

2026-06-16

AI Summary

This study presents the first systematic empirical analysis of the ecosystem, usage patterns, and associated security and censorship challenges of underground “airport”-style proxy services in China. Combining large-scale user surveys, Telegram channel scraping, active network measurements, and subscription-based performance testing, the research reveals that airports have become the dominant off-the-shelf proxy solution domestically, with over half of respondents reporting their use. While their multi-hop architectures often outperform direct connections in terms of performance, they introduce novel vulnerabilities—including payment data leakage, frequent service takedowns, and configuration complexity. The work delineates the technical infrastructure and user behavior within this ecosystem and identifies emerging risks to internet governance, providing crucial empirical insights into covert circumvention infrastructures.

Abstract

In China, a burgeoning underground market sells citizens subscription-based censorship circumvention proxies known as ''airports''. We present the first systematic study of this ecosystem, combining user surveys, social media analysis, and active network measurements. We find that airports are by far the most popular off-the-shelf censorship circumvention tool in China, used by over half of our 1,667~survey respondents, who cite their ease of use, performance, and access to geo-restricted services like ChatGPT and Netflix. By scanning the Internet and scraping Telegram announcement channels, we identify 3,431 active airports built on a handful of open-source toolkits. We subscribe to 35 airports and characterize their performance, which often surpasses direct connections through the Great Firewall due to a distinctive multi-hop architecture. However, airports also pose new challenges and security risks: they accept payment through commercial services like Alipay, suffer frequent government takedowns, and are difficult for clients to configure optimally. Many airports also deploy their own distinct censorship policies. Airports are far more widely used than other circumvention tools from the academic literature, but introduce new forms of fragility and control, offering both lessons and opportunities for future circumvention research.

Problem

• censorship circumvention
• airports
• Great Firewall
• proxy services
• network censorship

Innovation

• airport ecosystem
• censorship circumvention
• multi-hop proxy
• Great Firewall
• network measurement