Tehran, Iran – Iran’s government has moved to block Signal after Iranians flocked to the messaging platform following privacy concerns from Facebook-owned WhatsApp.
In a tweet, Signal said it has been “working around Iran’s censorship” since the app became the top downloaded content on Iranian app stores.
“Unable to stop registration, the IR censors are now dropping all Signal traffic,” the tweet said. “Iranian people deserve privacy. We haven’t given up.”
On January 14, Signal was ordered removed from Cafe Bazaar, Iran’s version of Google Play, and Myket, another well-known local app store.
“We thank you for understanding our limitations,” a message greeted Iranians who wished to download Signal.
The app was tagged by a filtering committee tasked with identifying “criminal content” that is headed by the country’s prosecutor general and consists of representatives from the judiciary, the communications ministry, law enforcement, the parliament, and the education ministry among others.
However, the judiciary sought to distance itself from the ban on Tuesday.
Spokesman Gholamhossein Esmaeili said under new chief Ebrahim Raisi since 2019, the judiciary has not “blocked any media, news outlet or messaging service and is not after blocking cyber space and any social messaging services”.
This is not the first time Signal is being targeted by Iranian authorities.
The app was previously blocked sporadically between 2016 and 2017, but the filtering largely flew under the radar as Signal did not have a considerable user base in Iran at the time.
The messaging service was later quietly unblocked and no official reason was ever provided by authorities.
Signal was used by a number of Iranians during protests in late 2017 and early 2018 in an effort to maintain secure communications, according to Mahsa Alimardani, an internet researcher with British human rights organisation ARTICLE19.
“Signal has always been advertised as the go-to application for dissidents or activists to stay secure from any state authority, especially the United States and its vast surveillance capabilities,” she told Al Jazeera.
“Before this migration by users disaffected by WhatsApp’s new privacy changes, Signal was already a day-to-day tool of civil society and activities,” said Alimardani, a PhD candidate at the Oxford Internet Institute.
Signal joins a large number of other top social media applications that have been blocked by Iranian authorities, including Telegram, Twitter, Facebook and YouTube.
Telegram was filtered in May 2018, shortly after protests that erupted in dozens of cities across Iran over economic, political and social grievances.
WhatsApp and Instagram remain the only leading unblocked foreign social media platforms in Iran.
The fact that Signal was blocked but WhatsApp remains usable has prompted speculation by Iranian users on social media that Iran’s government somehow has access to users’ information on WhatsApp.
Alimardani said the same rumour started circulating about Telegram before its blocking put it to rest.
“There is no factual basis for this rumour as it’s very unlikely Iranian authorities have the capability to go up against Facebook’s security capabilities, or for Facebook to collaborate with Iran to share data,” she said.
Instead, she said, it is more likely that Iranian authorities are trying to keep the number of unblocked apps limited before Signal grows too big in Iran.
With years of experience in dealing with internet restrictions by Iranian authorities and those imposed by international companies because of sanctions, Iranians have familiarised themselves with circumvention tools.
Many Iranians regularly use virtual private networks (VPNs) that mask the users’ IP to gain access to blocked content, including social media.
Despite being banned for almost two years, Telegram is still being used daily by tens of millions of Iranians. State entities, however, were legally barred from returning to the messaging service.
In this environment, Alimardani said the Signal ban will likely slow the growth of its user base and keep people on WhatsApp at first.
“However, stats from Telegram have shown that while usage went down directly following censorship, it eventually stabilised,” she said. “But the ban slowed the projected growth before censorship.”
There are currently no data on how many people use Signal in Iran, but it is believed its base is still much smaller than that of Telegram, which has been used in the country since its release in 2013.
Signal’s filtering has renewed fears over more potential restrictions for internet freedom in Iran.
Iran’s information and communications ministry has repeatedly tried to distance itself from blocking social media, saying it does not have the authority to make those decisions.
After authorities cut off internet access across Iran for almost one week during nationwide protests in November 2019, ICT Minister Mohammad Javad Azari Jahromi said it was not his decision.
The minster has so far remained silent on Signal’s filtering.
Last week, the judiciary brought charges against Azari Jahromi, but released him on bail, for allegedly refusing to block Instagram and otherwise restrict other social media.
The ministry said litigation from a group of 432 people from Ahwaz on the use of cyberspace in a September 2018 attack and 150 religious scholars from Kerman on digital “corruption” were among other reasons for the minister’s summoning.
Decision-making notwithstanding, internet security and digital rights researcher Amir Rashidi says the ministry is almost entirely in charge of technically implementing internet blocking practices in Iran.
Rashidi explained when an Iranian user wishes to use the global internet, their command is first routed to their local internet service provider, and then to the Telecommunication Infrastructure Company, affiliated with the ministry, which is the gateway.
“So in any of the two levels internet censorship can be implemented,” he told Al Jazeera.
Rashidi said, like Telegram, Signal’s popularity became its undoing with Iranian authorities.
“Traditionally, whenever the Iranian government can’t figure out what is going on or who is doing what, they fear maybe people are doing something against the government,” he said.