Worried About the Privacy of Your Messages? Download Signal
By BRIAN X. CHEN
Dec 7 2016
BY the time you finish reading this column, you would be foolish not to download the messaging app Signal onto your smartphone and computer.
The free encrypted messaging service has won the acclaim of security researchers and privacy advocates, including Edward J. Snowden. All have said that Signal goes above and beyond other chat tools in keeping electronic communications private.
And now more than ever, we may need it. That’s because hacks are on the rise — look at how the activist group WikiLeaks posted a trove of emails from Hillary Clinton’s campaign chairman, John D. Podesta, for all to see. Many are also watching for how government surveillance may grow under Donald J. Trump, who has chosen Mike Pompeo, who advocates greater surveillance, to lead the Central Intelligence Agency.
Signal is one of many encrypted messaging services, but it stands out for its uncompromising security and ease of use. The chat service retains virtually no information from users, including messages and address books, on its servers. What’s more, messages remain encrypted when passing through Signal’s servers, meaning that the app’s creators can’t read them.
“The default recommendation you’ll get from most security researchers for a messaging app is Signal,” said Joseph Bonneau, a postdoctoral researcher at the Applied Crypto Group at Stanford University. “It’s still the best in the field.”
That said, Signal is not perfect. It lacks some features of other messaging apps, like the ability to send stickers. And during my tests, the service had some glitches. But adding Signal to your folder of messaging apps is a must in an era when technology companies are collecting more personal information and government surveillance may expand.
Some people have already cottoned on to this. Signal experienced a 400 percent jump in daily downloads since Mr. Trump won the election, according to Moxie Marlinspike, who founded Open Whisper Systems, the nonprofit that developed Signal. To Mr. Marlinspike, the surge in downloads reflects anxiety among Americans about the implications of Mr. Trump’s presidency for personal privacy.
“Trump has threatened a lot of people and he’s about to be in control of the most pervasive and least accountable surveillance infrastructure in the world,” Mr. Marlinspike said. “A lot of people are justifiably concerned about that.”
How Signal Stands Out
Signal offers end-to-end encryption, meaning a message is scrambled so that it becomes indecipherable to anyone but its intended recipient when it is sent from your device, and it remains so when it passes through the app’s server and reaches the recipient.
When you initiate a conversation with someone on Signal, you and the recipient exchange so-called cryptographic keys. Only the person who receives your message holds the key to decrypt and read it. That means that if a government agency had a wiretapping order for your Signal messages, Open Whisper Systems would not have the key to decipher the messages and would be unable to comply.
Signal’s technology sets the standard for other messaging services, with its protocol being an open-source system that other companies can freely use. WhatsApp, Facebook’s Messenger and Google embedded Signal’s encrypted messaging system into their own apps this year.