Session is a

cross-platform Within computing, cross-platform software (also called multi-platform software, platform-agnostic software, or platform-independent software) is computer software that is designed to work in several Computing platform, computing platforms. Some ...

instant messaging Instant messaging (IM) technology is a type of synchronous computer-mediated communication involving the immediate ( real-time) transmission of messages between two or more parties over the Internet or another computer network. Originally involv ...

application emphasizing user confidentiality and anonymity. Developed and maintained by the non-profit The Session Technology Foundation, it employs a

blockchain The blockchain is a distributed ledger with growing lists of Record (computer science), records (''blocks'') that are securely linked together via Cryptographic hash function, cryptographic hashes. Each block contains a cryptographic hash of th ...

-based decentralized network for transmission. Users can send one-to-one and group messages, including various media types such as files, voice notes, images, and videos. Session provides applications for various platforms, such as

macOS macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

, and

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

, along with mobile clients available on both

iOS Ios, Io or Nio (, ; ; locally Nios, Νιός) is a Greek island in the Cyclades group in the Aegean Sea. Ios is a hilly island with cliffs down to the sea on most sides. It is situated halfway between Naxos and Santorini. It is about long an ...

and Android.

Features

Session does not require a telephone number or email address for account creation. Instead, it utilizes a randomly generated 66-digit alphanumeric number for user identification. Communication between users, including messages, voice clips, photos, and files, is end-to-end encrypted using the Session protocol. Session uses the Loki blockchain network for transmissions. In 2021, an independent review by the third-party Quarkslab verified these claims.

Development

Session started as a fork of another messenger,

Signal A signal is both the process and the result of transmission of data over some media accomplished by embedding some variation. Signals are important in multiple subject fields including signal processing, information theory and biology. In ...

, aiming to build upon its foundation. However, concerns about the centralized structure of Signal Protocol and potential

metadata Metadata (or metainformation) is "data that provides information about other data", but not the content of the data itself, such as the text of a message or the image itself. There are many distinct types of metadata, including: * Descriptive ...

collection led the team to deviate and create their own protocol, called "Session Protocol". This approach prioritized increased anonymity and decentralization. During development, the team encountered various challenges, leading to the necessity of abandoning or modifying many features.

Limitations

Session lacks support for

two-factor authentication Multi-factor authentication (MFA; two-factor authentication, or 2FA) is an electronic authentication method in which a user is granted access to a website or Application software, application only after successfully presenting two or more distin ...

, and its underlying protocols are still in a developmental phase. Following the migration from the Signal Protocol to its internally developed protocol,

forward secrecy In cryptography, forward secrecy (FS), also known as perfect forward secrecy (PFS), is a feature of specific key-agreement protocols that gives assurances that session keys will not be compromised even if long-term secrets used in the session ke ...

and

deniable authentication In cryptography, deniable authentication refers to message authentication between a set of participants where the participants themselves can be confident in the authenticity of the messages, but it cannot be proved to a third party after the event ...

were not implemented.

References

External links

* {{Instant messaging Cross-platform software Cryptographic software Free and open-source Android software Free instant messaging clients Free security software Free software programmed in Java (programming language) Instant messaging clients programmed in Java Internet privacy software IOS software Linux software MacOS software Windows software Secure communication Blockchain entities Instant messaging clients 2020 software