Meta Platforms (META.O) announced on Wednesday the commencement of the rollout of end-to-end encryption for personal chats and calls on both Messenger and Facebook. This heightened security feature, ensuring that only the sender and recipients can access messages and calls, is now immediately available. 

However, Meta acknowledges that the process of implementing default end-to-end encryption may take some time to be fully carried out across all Messenger accounts. While users previously had the option to activate end-to-end encryption for individual messages, Meta's latest update aims to establish this advanced privacy measure as the default setting for all users. This signifies a noteworthy enhancement in safeguarding user data. 

In introducing encryption, Meta emphasized that the content of messages is now inaccessible to everyone, including the company itself, unless a user opts to report a message, as mentioned by Loredana Crisan, the head of Messenger, in a post unveiling this update. To make this decision, Meta collaborated with external experts, academics, advocates, and governmental entities. Their joint efforts aimed to pinpoint potential risks, ensuring that the enhancement of privacy goes hand-in-hand with maintaining a safe online environment, as highlighted in Crisan's announcement. 

Meta Platforms' move to introduce default encryption on Messenger has drawn criticism from various quarters, with notable voices such as Home Secretary James Cleverly and James Babbage, director general for threats at the National Crime Agency, expressing concerns about its potential impact on detecting child sexual abuse on the platform. 

In a disappointed tone, Home Secretary James Cleverly highlighted the significance of Meta's decision as a setback, particularly in light of collaborative efforts to address online harms. Despite this disappointment, he stressed a continued commitment to working closely with Meta to ensure the safety of children in the online space. 

James Babbage, director general for threats at the National Crime Agency, echoed this sentiment, characterizing Meta's choice to implement end-to-end encryption on Facebook Messenger as highly disappointing. He emphasized the increased challenges their team now faces in fulfilling their role of protecting children from sexual abuse and exploitation due to this development. 

End-to-end encryption (E2EE) in messaging ensures the confidentiality of messages for all parties involved, including the messaging service. Within the framework of E2EE, a message undergoes decryption exclusively for the sender and the designated recipient, symbolizing the two "ends" of the conversation and giving rise to the term "end-to-end." 

"When E2EE is default, we will also use a variety of tools, including artificial intelligence, subject to applicable law, to proactively detect accounts engaged in malicious patterns of behaviour instead of scanning private messages," the company wrote. 

While numerous messaging services claim to provide encrypted communications, not all genuinely offer end-to-end encryption. Typically, a message undergoes encryption as it travels from the sender to the service's server and subsequently from the server to the intended recipient. Nevertheless, in certain instances, the message may be briefly decrypted when it reaches the server before undergoing re-encryption. 

The nomenclature "end-to-end" encryption is apt because it renders it practically impossible for any intermediary to decrypt the message. Users can place confidence in the fact that the messaging service lacks the technical capability to read their messages. To draw a parallel, envisage sending a letter secured in a locked box, of which solely the sender and the recipient possess the key. This physical barrier for anyone else mirrors the digital functionality of E2EE.