Deng Tong, Jinse Finance
On November 27, 2025, Vitalik posted on X, showing his support for two decentralized messaging applications, Session and SimpleX Chat, and donated 128 ETH to each of them.
Vitalik points out that digital privacy protection in encrypted messaging is crucial. Two important directions for future development in this field are: (i) permissionless account creation; and (ii) metadata privacy protection.
Neither of these two software programs is perfect; they have a long way to go before achieving truly optimal user experience and security. Robust metadata privacy protection requires decentralization, which is inherently difficult to achieve, further complicated by users' expectations of multi-device support. Defending against Sybil/DDoS attacks on the message routing network and the user end (without mandatory reliance on phone numbers) also adds to the difficulty. These issues require more attention. Best wishes to all the teams dedicated to solving these important problems.
1. What are Session and SimpleX Chat?
1. Session
Development of Session began in 2018, initiated by the Australian-based Oxen Privacy Tech Foundation. The project was initially a fork of another instant messaging software, Signal, designed to expand upon it. However, due to concerns about the centralized structure of the Signal protocol and potential metadata collection issues, the team decided to take a different approach, creating their own protocol, the "Session Protocol." This approach prioritized increased anonymity and decentralization. During development, the team encountered various challenges, leading to the abandonment or modification of many features. In 2024, facing increasingly stringent privacy and surveillance legislation in Australia, the Swiss-based Session Technology Foundation took over the development and release of the application.
Session is a decentralized, end-to-end encrypted instant messaging tool designed to minimize metadata leaks—metadata refers to information surrounding content, such as IP addresses or sending times. Session allows account creation without phone numbers or email addresses. It uses a randomly generated 66-bit alphanumeric combination 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 transmission. These claims were confirmed in an independent review by Quarkslab in 2021. In 2025, Session announced its migration to its own network, Session Network—a decentralized, open-source blockchain network designed specifically for transmitting encrypted data within the Session instant messaging software.
Session also issued a token, SESH. According to CoinGecko data, the token rose to a high of nearly $0.30 due to Vitalik X's tweets, before falling back to $0.1961 as of press time.
2. SimpleX Chat
SimpleX Chat is also an open-source instant messaging tool that emphasizes "no user ID" – no phone number, email address, or random username/ID. It supports end-to-end encryption (E2EE) and its protocol is designed to withstand future quantum computing.
According to the SimpleX Chat white paper, the SimpleX Message Passing Protocol (SMP) is a one-way message passing protocol that relies on an intermediary server. Messages are passed through a one-way queue created by the receiver. The SMP protocol allows an SMP server to act as a proxy, sending messages using "private routing" to protect the sender's transmission information (IP address and session) from eavesdropping by a server chosen (and potentially controlled) by the receiver.
SMP runs on top of a transport protocol that provides integrity, server authentication, confidentiality, and transport channel binding. SimpleX servers are one such protocol. A SimpleX network refers to a collection of SimpleX servers used to support SMP. SimpleX client libraries communicate with SimpleX servers via SMP and provide a low-level API not typically used by applications. SimpleX Agents interact with SimpleX Clients, providing a higher-level API for application use. They are usually embedded as libraries but can also be abstracted as native services. SimpleX agents communicate with other agents through end-to-end encrypted envelopes provided by the SMP protocol—the syntax and semantics of messages exchanged between agents are defined by the SMP agent protocol.
Next year, SimpleX will launch "vouchers" that users will need to purchase and donate to the community (such as the Bitcoin community) to host the servers they need.
II. Behind Vitalik's endorsement: Protecting privacy in instant messaging is becoming a necessity.
Privacy issues surrounding instant messaging applications have been a hot topic, influenced by previous EU measures such as "chat controls." This measure would force platforms like Telegram, WhatsApp, and Signal to allow authorities to review messages before they are encrypted and sent.
The reason Session and SimpleX Chat won Vitalik's favor lies in their precise alignment with his two core directions: "permissionless account creation" and "metadata privacy protection." Permissionless account creation means users don't need to provide any personal identification credentials, completely breaking the identity binding shackles of traditional communication tools and avoiding the chain of risks caused by identity information leaks. Metadata privacy protection goes beyond simple content encryption, extending protection to metadata levels such as message sending time, sender's IP address, recipient's address, and message size—information that may seem insignificant, but through big data analysis, can reveal a user's social relationships, behavioral habits, and even asset status; its privacy value is no less than the communication content itself.
Back in April, Vitalik proposed a roadmap aimed at making it easier and more natural for ordinary users to conduct private transactions and anonymous on-chain interactions without requiring major changes to the network's core protocols. The proposed roadmap covers four main forms of privacy: privacy for on-chain payments, partial anonymization of on-chain activities within applications, privacy for on-chain reads, and network-level anonymization.
Subsequently, Ethereum has been moving towards a greater emphasis on "privacy": at the Ethereum Developers Conference from November 17 to 22, Vitalik released Kohaku, an Ethereum privacy-preserving cryptographic tool – a new privacy and security toolkit for Ethereum wallets.
On November 25, while Wall Street banks such as JPMorgan Chase, Citigroup, and Morgan Stanley were still grappling with the aftermath of the massive data breach, Vitalik delivered a crucial message: "Privacy is not a feature; privacy is basic hygiene."
Alexander Linton, president of the Session Technology Foundation, pointed out: “Unfortunately, regulatory and technological advancements are currently threatening the future of private instant messaging. However, the challenges facing private instant messaging are solvable, and I believe Vitalik is well aware of the importance of decentralization in this fight. Everyone working in private messaging currently faces some kind of threat due to regulatory measures such as chat controls, but this support helps us focus on our mission.”
Session co-founder Chris McCabe noted, “It’s amazing how clearly we see that Vitalik and many others around the world understand what true privacy is and what people need to live freely.” Raising global awareness of encrypted, decentralized messaging should be a crucial next step. “If we’re going to send a message to the world, it’s that you don’t have to be a commodity; you can be who you want to be and express yourself freely. Privacy is a right, and you just need to know it exists.”
Zac Williamson, co-founder of Aztec Network, an Ethereum Layer 2 network focused on privacy protection, points out: "People's lives are increasingly dependent on digital spaces. These spaces are extremely vulnerable to surveillance that is unparalleled in the real world. Privacy is crucial because it allows people to act freely in their online interactions, rather than becoming digital commodities whose data is collected, sold to the highest bidder, and used to harm users' interests."
III. Conclusion: Is the next big trend the "privacy" sector?
For ordinary users, Session and SimpleX Chat offer a brand-new option for private communication, especially in protecting sensitive information, and their future value is already beginning to emerge. For the encryption industry, these two "explorers" provide more ideas for the complete development of Web3 privacy infrastructure.
While the privacy communication sector currently lacks the grand narrative of AI and DeFi, Vitalik and the Ethereum team's focus on it may attract more projects and capital. Amidst increasing global regulation and ongoing data breach scandals, decentralized privacy communication could be the next industry hotspot as more developers enter the field.
