Paris (AFP)

Politicians, lawyers, journalists and surely some criminals: people concerned about the confidentiality of their exchanges are installing more and more the encrypted messaging application Signal, a pioneer of the genre and appreciated by experts even if it does not avoid all the pitfalls of online security.

Discussing discreetly on the internet means knowing how to follow the latest fashion: because of the network effect which means that interest in a social application increases at the same time as its number of users, there is no point in having found the rare pearl if you are the only one to use it.

In this little game, the Signal application, which replaces the functionality of SMS on smartphones and makes it possible to encrypt "end to end" messages or audio and video calls, could be on the way to gain the confidence of people concerned with confidentiality, sensitive data sharers and other holders of professional secrets.

In February, the European Commission recommended it to its teams, in particular to secure exchanges with people outside the organization. AFP journalists also testify to massive installations among politicians, and - to a lesser extent - among their judicial or police sources.

The competing applications "Telegram and WhatsApp are considered risky because their source code remains proprietary, while Signal is free and cannot be accused of partisanship vis-à-vis this or that state. I myself recommend migrating from several month ", explains to AFP a historic framework of LREM, the party of French President Emmanuel Macron.

The image of the Russian Telegram application, whose discussion loops initially appealed to the presidential party and politicians of all stripes, was tainted by its widespread use by jihadists and its troubled relations with Russian power.

As for the American Whatsapp, which claims two billion active users in the world, it is the vector of several resounding hacks (including that of the phone of the boss of Amazon, Jeff Bezos, in January) and criticized on its management of personal data since its acquisition by Facebook in 2014.

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Signal's origins date back to 2010, when an American group of mobile security researchers called Whisper System created RedPhone messaging.

Following the acquisition of the young company by Twitter in 2011, one of these researchers, Matthew Rosenfeld (a hacker-browser with blonde dreadlocks better known by the pseudonym Moxie Marlinspike) founded the organization Open Whisper Systems in San Francisco, California. to continue developing free messaging.

Funded by donations, it launched Signal in 2015. Without a marketing campaign or communication budget, the completely free application is becoming popular among whistleblowers and journalists, thanks in particular to the public support of Edward Snowden, originally revelations about the US secret service’s procedures for monitoring telecommunications.

"This application is one of the most recommended in the security world. Its code has been audited by third parties many times. This is where trust comes from," said computer expert Baptiste AFP. Robert.

For cybersecurity journalist Damien Bancal, the tool is "essential" to secure his conversations during their transmission, even if he must remain vigilant on its developments.

Signal relies in particular, like Telegram or Whatsapp, on a centralized architecture whose servers can become a target for hackers or censorship. The application also requires communicating a phone number to initiate a conversation, posing problems of anonymity and potentially hacking.

In 2018, the small organization received a $ 50 million endowment from Brian Acton, one of the founders of WhatsApp who had left Facebook a few months earlier: he became executive chairman of the new "Signal foundation" with the aim to conquer "billions of users."

With these new means, messaging wants to become more user-friendly and popular. It includes "stickers", small drawings to exchange, allows you to send ephemeral messages and create discussion groups.

The number of users is not known, but according to the application market specialist AppAnnie, Signal is progressing in the rankings: it now appears in 110th place worldwide in social applications in number of downloads (59th in the United States and 40th in France ).

© 2020 AFP