It will soon be possible to use WhatsApp without owning a smartphone. The most popular application in the hearts of the French is indeed rethinking its architecture to end its dependence on the smartphone, via a new feature that will allow its users “to simultaneously use WhatsApp on their phone and up to four other devices without a phone, even if their phone’s battery is dead ”.
“For years, people have been asking us to create a true multi-device experience, which would allow WhatsApp to be used on other devices, without the need for a smartphone connection. Today, we are announcing the launch of a public beta, in limited testing, for the new multi-device functionality of WhatsApp, ”the teams from WhatsApp’s parent company, Facebook, said last week. And to note that the development of this new functionality has led them to “rethink the architecture of WhatsApp and to design new systems to allow an autonomous experience on several devices, while preserving confidentiality and end-to-end encryption”.
While WhatsApp has until now used “a smartphone app as the primary device, making the phone the source of truth for all user data” while apps installed on other devices “simply mirror its content to their own. user interface ”, this will soon no longer be the case. “The new multi-device architecture of WhatsApp removes these obstacles”, thus note the engineers of Facebook.
If each WhatsApp user was until now identified by a single identity key, the new functionality implemented by the American giant now ensures that each device on which the instant messaging application is installed has its own key. “The WhatsApp server maintains a correspondence between each person’s account and all the identities of their devices. When a person wants to send a message, he obtains his device list keys from the server, ”explains the management of the social network.
What about security? Facebook claims to have done things big, for example by extending security devices to allow users to have control over all devices connected to their account. The American giant’s teams have also deployed automatic device verification technology while retaining the traditional QR code to associate new devices. Users will now be able “to see all the companion devices linked to their account, as well as the date of their last use, and will be able to disconnect remotely if necessary”, argues Facebook.
Finally, the American giant indicates that it still uses the same scalable Sender Key encryption scheme of the protocol of its main competitor Signal. “WhatsApp multidevice uses a ‘client-fan-out’ approach, whereby the sending WhatsApp client encrypts it and transmits it n times to n different devices – that is, those designated in the device lists of the sender and the recipient ”, indicates the management of Facebook, which notes that“ each message is then encrypted individually, using the paired encryption session established with each device ”. If the beta of this major new feature for WhatsApp includes only a small number of participants, it should soon be extended to the general public, indicates the management of the American giant.