The Promise of Blockchain-Based Email
If you look around the blockchain ecosystem, you might notice that one seemingly obvious use case for blockchain technology is surprisingly rare: email.
While a handful of startups are working to build decentralized email platforms based on blockchain technology, they are few and far between. They have received much less attention than organizations that seek to disrupt other technology niches, such as online search and ad tech .
This is surprising. In some key respects, a blockchain-based email solution seems like an obvious proposition. It would address several problems associated with traditional email services on which users send, receive and store email using centralized servers owned by a commercial company.
The first challenge is the privacy of users. Today, most consumers use email services, like Gmail and Yahoo Mail, that are free of direct cost. (You can also set up your own private mail server if you want, but most consumers don't know how to do that and the host infrastructure could prove costly.)
Instead, users pay in the form of personal data. Email providers collect personal information about users and use that data to serve ads to them. Sometimes data collection includes, but is not limited to, reading users' emails . Most email providers promise that users' messages are parsed only via automated tools, but this can still feel like a privacy intrusion for consumers.
A blockchain-based email solution would address this problem by obviating the need to rely on commercial companies to provide email services. The infrastructure required to host email servers and store messages could be distributed across a blockchain, where no single party would have the ability to read each user's messages.
Emails and the data attached to them can be lost in a number of ways. Users might accidentally delete them. They could be overwritten by storage servers that run out of space. Glitches on the infrastructure of email providers might lead to data loss (which has happened in the case of services like Gmail, albeit not in a way that led to permanent data loss).
Some of these risks would disappear if emails were stored on a distributed database. The failure of a central email server would not cause data loss, because there would be no central server on a blockchain-based email solution. Server storage capacity would be virtually unlimited, as long as the blockchain that was used to store data could grow as needed. It might even be possible to recover deleted messages via a method such as accessing an off-chain node that has preserved email data intact.
A third common challenge with email today is authenticity. It's trivially easy to set up an email account in someone else's name, and it's difficult for an email recipient to confirm that an email originated from where the sender claims it did. Timestamp and routing data in email headers could also be manipulated.
A blockchain-based email system could provide built-in message authenticity that would be virtually tamper-proof. Because the blockchain serves as an immutable record of transactions, it would become much easier to confirm exactly when and by whom an email was written or received. Short of hacking the blockchain itself, no one could modify blockchain-based email records.
Existing Decentralized Email Solutions
Despite the apparent value of a blockchain-based email platform, relatively few projects exist in this market.
Those that do include the following:
- John McAfee SwiftMail , a private messaging service founded by John McAfee, according to the project's website. It appears that it can only exchange messages with other SwiftMail accounts, so this is not exactly a general-purpose email service. But it's close.
- CryptaMail , which does appear to be a true email service. It's currently in beta.
- Proemtheus , which offers email services built on the blockchain. The company also appears to be building a larger decentralized platform on which cloud storage and other online applications can be run.
So far, the number of real-world users of these services appears to be small. That may be due, in part, to the fact that some potential users have expressed concern about whether the companies truly protect users' privacy and what would happen to users' messages if the companies shut down.
Decentralized email servers have other kinks to work out, too. Perhaps the largest is the massive amount of data that would need to be stored on the blockchain in order to run a large-scale decentralized email platform. If you want to store all users' messages on a blockchain, your storage needs will quickly climb into the terabytes. It's unclear whether today's blockchains could handle that level of scale.
On the other hand, this challenge is similar to the one that blockchain-based cloud storage services face, and they have strategies in place to address it. Moreover, in the case of email, it should be possible to decentralize email without actually storing all messages on the blockchain; message transactions could be recorded on the blockchain while messages themselves live elsewhere for permanent storage.
Decentralized email services also need to be able to prove to users that data is indeed private. The best way to do this is to make the source code for blockchain-based email servers available. For now, however, that is not happening; none of the services listed above appear to be open source.
Finally, in order to protect the privacy of individual users while registering emails on a blockchain, a decentralized email system would require more sophisticated access controls for blockchain-based data than most blockchains provide natively today. In other words, you'd need a way to make sure that authorized users could read their own email, but not the emails of other people who also use the decentralized service. This obstacle should be easy enough to overcome, however; access control features for blockchains can be implemented , and they may become more common as blockchains evolve.
Blockchain-based, decentralized email systems are promising, yet to date, little progress has been made in implementing them. That might change as specific problems, such as data storage scalability and proof of user privacy, are overcome by developers seeking to decentralize email for everyone.