Email, privacy & protocol glossary

Plain-English definitions for the email, privacy and protocol terms you will see across Reeva — and across any modern mail and cloud product.

Mail envelope surrounded by protocol badges — JMAP, IMAP, SMTP, TLS, E2EE, DKIM, SPF, DMARC, MX, custom domain, alias, mail forwarder, CalDAV and CardDAV — all defined in this glossary

JMAP — JSON Meta Application Protocol: Modern mail protocol over JSON / HTTPS, standardized in RFC 8620 / 8621. Replaces IMAP with batched requests, real push notifications, and a single round-trip for typical operations. Reeva speaks JMAP natively.
IMAP — Internet Message Access Protocol: Long-standing protocol for reading mail from a server, designed in 1986. Stateful, chatty, no real push (clients poll). Still ubiquitous. Reeva supports IMAP for compatibility with Thunderbird, Apple Mail, Outlook, K-9 Mail and similar clients.
SMTP — Simple Mail Transfer Protocol: Protocol for sending and relaying email between servers (and from clients via "submission" on port 587). All real email passes through SMTP at some point. Reeva implements modern SMTP submission with mandatory TLS.
TLS — Transport Layer Security: Cryptographic protocol that encrypts data in transit between client and server (and between mail servers). HTTPS is HTTP over TLS. Reeva enforces TLS on all submission and delivery paths.
E2EE — End-to-end encryption: Encryption where only the sender and recipient hold the keys — the provider cannot decrypt the content. Mail E2EE typically uses OpenPGP or S/MIME and only protects messages between users who exchange keys. Reeva protects mail with TLS in transit and encryption at rest; for cross-user E2EE, use a PGP-capable client.
Encryption at rest: Server-side encryption of data stored on disk. Protects against physical theft of drives or backups. Reeva stores mail and files encrypted at rest.
DKIM — DomainKeys Identified Mail: Cryptographic signature added to outgoing email so receiving servers can verify the message was sent by an authorized sender for your domain. Reeva auto-generates DKIM keys for custom domains and produces the DNS record to publish.
SPF — Sender Policy Framework: DNS record that lists which mail servers are allowed to send mail on behalf of your domain. Receiving servers check SPF to reject obvious spoofing. Pairs with DKIM and DMARC.
DMARC — Domain-based Message Authentication, Reporting & Conformance: DNS policy that tells receivers what to do (none / quarantine / reject) when a message fails SPF and DKIM. Sends aggregated reports back to a configured address. Required by major providers for high-volume senders.
MX record — Mail Exchanger record: DNS record that tells other servers where to deliver mail for your domain. Pointing your MX to Reeva is how custom-domain mail starts working.
Custom domain — Custom domain email: Sending and receiving mail at your own domain (e.g. [email protected]) instead of a provider-owned domain. Reeva supports custom domains on paid plans, with auto-generated MX, SPF, DKIM and DMARC records.
Alias — Email alias: Additional address that delivers to the same mailbox. Useful for keeping your real address private when signing up for services, or separating roles. Reeva lets you create aliases on your own domain or on @reeva.email.
Mail forwarder: Address that automatically re-sends incoming mail to one or more destinations. Forwarders survive provider switches and let you give out a single durable address.
CalDAV — Calendar Distributed Authoring and Versioning: Open protocol for accessing calendar data. Supported by Apple Calendar, Thunderbird, GNOME Evolution and most calendar apps. Reeva exposes calendars over CalDAV.
CardDAV — vCard Extensions to WebDAV: Open protocol for syncing contacts. Pair with CalDAV for full PIM sync over open standards. Reeva exposes contacts over CardDAV.
Stalwart — Stalwart Mail Server: Open-source mail server written in Rust that speaks JMAP, IMAP and SMTP. Reeva is built on Stalwart, which is auditable and actively maintained.

Ready to try standards-based mail?

Reeva speaks the protocols above natively — JMAP, IMAP, SMTP, CalDAV and CardDAV — and runs on the open-source Stalwart engine. Encrypted mail, calendar, contacts, password vault and file cloud in one account.

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