I nearly got phished earlier this year. 24+ years in software engineering, I know exactly how phishing and spam work and what to look out for, and it still almost worked on me. That's what made me question the entire email landscape rather than just my own attention.

It seems every attempt to fix it so far requires either a complex process, joining a closed system, or accepting that mail can never be trustworthy. Or maybe we just need something new and open alongside SMTP that meets our modern-day needs but can bridge and interoperate with SMTP as well.

I'm not saying I have all the answers, or that this is the best way forward. But given the landscape and the clear need for something different, DMCN was born out of the frustration and the hope that we can actually find a way to make email trustable.

DMCN is a federated network of servers (currently seeded by me) that communicate via the open DMCN protocol. The DMCNP puts digital identity (public key cryptography) front and center into the protocol, making every stage of email communication between DMCN mailboxes visible and verifiable.

This is not a new invention or a new clever way of doing things. It's merely orchestrating and arranging existing concepts and tools in a way that gives users all the benefits with as little of the complexity and process as possible.

A private key represents a mailbox, and the public key is attached to an email address (not all that different from PGP so far). The discovery part is where it differs. A domain’s DMCN email fleet (discoverable through DNS) holds all the public records for a domain’s mailboxes and their public keys, signed by the key holders themselves, and the domain owner (where applicable). Accessible to any fleet that speaks the same protocol and is verifiable using information from DNS and the public records.

An optional bridge to SMTP is available to allow interoperability with SMTP, which trades in the digital identity for compatibility.

Emails are signed by the author on their own device, encrypted to each recipient (or the bridge when the email is not a DMCN recognized address) and sent to the bridge or the recipient’s domain email servers. There the emails are stored in their encrypted form, waiting for the mailbox owner to authenticate with their private key, download the encrypted emails, open and verify their integrity, sender details and signatures, and ask the recipient what they want to do. Trust the sender, preview the content, or block it silently.

Keys stay on your own devices, with only one optional exception when pairing another device.

You can check out the open protocol and run the reference server available at https://dmcn.dev.

Quick start (for localhost only):

1. `docker run --rm -p 8080:8080 -e DMCND_DEV=true ghcr.io/dmcnp/open-dmcn`

2. Visit `http://localhost:8080` in your browser, and another one in an incognito window.

3. Register an email address in each (e.g. `one@localhost`, `two@localhost`) secured by passkey or passphrase.

4. Send email between them.

For a live setup, a full set of instructions is available at https://dmcn.dev/quickstart but requires a VPS with a public IP, a domain with DNS, and a bit of your time to get it all set up.

I also run a hosted version at https://dmcn.email if you'd rather not self-host. It does require you to pick an email address but nothing requires you to provide an existing email account, phone number, or any other information. Your browser will create the private key, you choose the email address and secure your local copy of the private key with a passkey or a password. The only things the client sends are the email address you just signed up for, the public key, and an agreement of the terms of service. All of which are signed by your newly minted private key.

Feel free to email me at `merten.vg@dmcn.me` when you have a live account.

Show HN: Email where an address is a keypair, with an SMTP bridge