Project

Glossary

The terms used throughout this documentation, defined precisely, including the ones that mean something narrower here than they do elsewhere.

Protocol terms

Envelope

The sealed blob written into a Mail event. Opaque to the contract, which checks only its length. See Envelope format.

Payload

The plaintext inside an envelope: subject, body, timestamp and the routing commitment. Never leaves the browser unsealed.

Mailbox key

The X25519 keypair used for encryption. Derived from a signature; distinct from the wallet's signing key.

Key version

A monotonic counter per wallet, incremented on rotation and never reset. Lets old mail stay readable.

Name epoch

A counter per name, incremented on every ownership change, so a client can detect that a contact changed hands.

Stamp

Value escrowed by an unknown sender to reach a recipient. Per message, never aggregated. See Stamps.

mailId

The sequential identifier of a message, and the key for its escrow row.

convoId

Keccak of the sorted address pair. Groups a thread. Derivable from the event topics, so it is not indexed separately.

Release grace

Seven days after a name is released during which only the previous owner may re-register it.

Credit

Value owed to an address after a push payment failed. Pulled by its owner, so a hostile recipient cannot strand funds.

Skeleton

A confusable-folded form of a name, used by clients to warn about lookalikes. Advisory only, never enforced on chain.

Cryptographic terms

X25519

Elliptic-curve Diffie-Hellman on Curve25519. Produces the shared secret two parties use to encrypt to each other.

XSalsa20-Poly1305

The authenticated cipher inside NaCl crypto_box. Provides confidentiality and integrity together.

HKDF-SHA256

The key derivation function of RFC 5869. Turns the signature into uniform key material.

EIP-712

Typed structured-data signing, so the wallet displays what is being signed rather than an opaque hash.

Ephemeral key

A keypair generated for one message and discarded. Two ciphertexts are produced from it: one for the recipient, one for the sender.

Small-order point

A curve point that forces the shared secret to a fixed value. Six are known on Curve25519 and all six are rejected.

Clamping

Fixing specific bits of an X25519 scalar so it is a valid private key.

Nonce

A 24-byte number used once per encryption. Random per message here.

Forward secrecy

The property that compromising a long-term key does not expose past messages. bMail does not provide this within a key version.

Chain terms

Event log

Data emitted by a transaction, cheap to write and readable off chain but not by contracts. Where every message body lives.

Topic

An indexed event field. Mail indexes from, to and mailId, which is what makes inbox filtering cheap.

Contract storage

Persistent contract state at 20,000 gas per fresh slot. Used only for small structural facts.

BSC

BNB Smart Chain. Chain ID 56.

opBNB

The layer-2 rollup on BNB Chain. Far cheaper per byte, which suits routine messaging.

Greenfield

BNB Chain's decentralised storage network. The intended home for large attachments; not part of v1.

Terms used narrowly here

Precision matters more than reassurance

Several words are used loosely across the industry. Where this documentation uses them, it means the narrower thing.

Term	What it means here	What it does not mean
Encrypted	Message contents are sealed to the recipient's key in the browser	That metadata is hidden. Sender, recipient, time and size are public.
Private	Nobody but the recipient can read the contents	Anonymous. The social graph is fully visible.
Decentralised	No server holds mail; the protocol runs without an operator	That the RPC node you query is trustless, or that the frontend cannot be compromised.
Own your address	The name is minted to your wallet and no operator can reassign it	That it is recoverable. Lose the wallet and it is gone.
Gas only	No subscription and no protocol fee for names of five characters and up	Free. Gas is a real cost, and premium names carry a fee.
Audited	Three rounds of self-directed adversarial review, documented in full	That an independent firm has reviewed it. None has.