TAIPEI – The messaging app Signal became unusable for many people in mainland China this week, suffocating one of the last widely used messaging apps that could send and receive the encrypted messages across the country without a virtual private network.
The government’s apparent move to block Signal is increasing its hold on public and private talks in China, where many social media and messages, including Facebook,
Twitter and, more recently, the popular social audio platform Clubhouse, have been banned.
Signal users in mainland China began reporting problems with sending and receiving messages in the app on Monday night. Using a virtual private network, or VPN, a tool that enables Internet users to bypass China’s extensive system of web filters, solved problems that led to the app being blocked in China.
Some also reported problems with registration, another common censorship practice that affected Clubhouse last month, where users could not log in to their phone numbers because the verification code was never received.
A person familiar with the matter began Sunday with registrations and network blocks stopped. The Cyberspace Administration of China, the country’s Internet regulator, did not immediately respond to a request for comment.
The Chinese Foreign Ministry on Tuesday referred a question about the apparent ban to the department concerned, but said that China’s internet is open and that the government operates the internet according to the law.
Signal uses end-to-end encryption, which prevents third-party access to transmitter-receiver communications. It contains features such as disappearing messages and media, and has been promoted as a tool for secure and private communication. Similar encrypted messaging programs, such as Telegram and Facebook Inc. WhatsApp, is also inaccessible in China without a VPN.
Signal became popular among Chinese users last year after the US government said it would ban WeChat,
The most popular messaging app from China, launched by Tencent Holdings Ltd. also jumped in Hong Kong after lawmakers passed legislation on national security, which suppressed protests against democracy.
WeChat uses client-to-server encryption, which gives Tencent full access to data between senders and receivers. The app is ubiquitous in China and is primarily a necessity for everyday life through its messaging and payment services. It is also known for censoring sensitive issues, such as political criticism or during the outbreak of the coronavirus in Wuhan.
In February, Chinese sensors blocked Clubhouse after the app began gaining a foothold in the country, leading to discussions on sensitive topics usually restricted in China, such as the treatment of Uyghur Muslims in China or Tiananmen Square.
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“It has always been a surprise that Signal has taken so long, as the purpose of the app is to facilitate encrypted communication.”
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As with Clubhouse, some saw the loss of Signal as inevitable due to China’s extensive censorship apparatus and the tightening of control over its Internet users.
“It’s always been a surprise that Signal has lasted so long, since the app’s purpose is to facilitate encrypted communication,” said James Griffiths, author of “The Great Firewall of China: How to Build and Control an Alternative Version” , said. from the internet. ”
Yaqiu Wang, a China researcher at Human Rights Watch in New York, said Signal is the latest encrypted messaging app she can easily use to securely connect with friends and activists in mainland China.
Although Signal can still operate with a VPN, it has become more difficult to access in China in recent years after China tightened its rules on the instrument. At least hundreds of VPNs have been removed from app stores, while VPN users and providers have been fined.
“All of this is an indication that it will be harder and harder for people to talk to people safely about sensitive issues,” Wang said. “I’m really worried about communicating with people in China.”
Although there was no clear catalyst for the apparent ban, some experts speculated that Signal’s recent popularity among mainland users may have contributed.
According to research firm Sensor Tower, downloading Signal on iOS, Apple’s operating system, began to increase in China in recent years before declining in February and March. Signal installations peaked at 52,000 in August after the U.S. WeChat ban was announced and rose again in January, with about 49,000 installations.
According to Sensor Tower data, Signal users in China are a fraction of that on WhatsApp or Telegram. Signal download on iOS reached a total of about 510,000 in China, compared to 9.6 million WhatsApp installations and three million Telegram installations.
Signal was also blocked in Iran in January. The company said it had launched a solution for the network block and was investigating more ways to circumvent the ban.
Write to Stephanie Yang by [email protected]
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