simplex-chat/docs/rfcs/2026-05-21-public-namespaces.md

Public Namespaces for SimpleX Network

Motivation

SimpleX has no user identifiers - users exchange invitation links out-of-band to connect. Short links help but are unmemorable. Public namespaces map human-readable names to SimpleX addresses.

Names also solve censorship at two levels. A short link is controlled by one SMP router - that router can delete it. An on-chain name can't be deleted by any router. If the link is removed, the owner points the name to a new link on a different router. At the network level, links can be URL-filtered, but names resolve through SMP proxy chains - censoring a name requires controlling all resolvers the user can reach.

DNS-based naming is vulnerable to domain seizure and requires WHOIS entries. Blockchains provide censorship-resistant globally unique names.

Product requirements

MVP

• Names: TLD .simplex (e.g., privacy.simplex, my-channel.simplex). Subdomains: support.acme.simplex. In markdown, .simplex can be omitted: #privacy = privacy.simplex.
• Name rules: see Name rules.
• Two address types: each name stores channel links (set) and contact links (set). Client uses the first; set provides forward-compatible redundancy. Either can be empty.
• Optional metadata: admin SimpleX address, admin email.
• Registration: commit-reveal to prevent frontrunning. Length-based ETH pricing. Annual renewal. Dutch auction on expiry.
• Launch gating: requires SimpleX test NFT. Up to 5 paid + 5 test names per holder. Test names free, auto-removed after 3 months, use testing namespace.
• Reserved names: common verticals (books, games, music, movies, news, etc.) reserved for community-operated channels managed by SimpleX Network Consortium.
• Only 7+ character names can be registered during "launch phase".
• Resolution: client queries two independent name servers (Ethereum light clients) via two SMP proxies. Agreement = trusted. Disagreement = warning.
• Double resolution: name -> short link (on-chain), short link -> connection data (existing protocol).
• Verification: if on-chain link matches profile address, name is verified. Manual "verify" button + optional auto-verify on profile open.
• Markdown: #name (.simplex implied), #name.simplex (explicit), #name.testing for test namespace. In CLI, # is local in group commands, global in /c and message bodies.
• Search: #name.simplex auto-resolves. Disable in "More privacy" settings.
• Router role: names added to ServerRoles. Not all routers support it.
• Contract: ENS fork on Ethereum mainnet. ETH payment. Upgradeable.

Post-MVP

• Multiple links: redundant entries per name. Forward-compatible schema in MVP where practical.
• Contact syntax: :name.simplex, :my-name.simplex. Same namespace, different link type. MVP parser supports this syntax; resolution works; UI support is post-MVP.
• Community Credits: replace ETH for private registration.
• Unicode expansion: add scripts as user base grows.

Part 1: Blockchain contract

Overview

ENS fork on Ethereum mainnet. Retains commit-reveal, pricing, expiry, Dutch auction. Compatible with ENS dApp. Upgradeable.

ENS source:

• Contracts: https://github.com/ensdomains/ens-contracts
• dApp: https://github.com/ensdomains/ens-app-v3
• JS library: https://github.com/ensdomains/ensjs

Contract state

Name record (ENS structure + SimpleX resolver fields):
  owner          : address
  channelLinks   : string[]
  contactLinks   : string[]
  adminAddress   : string       -- optional
  adminEmail     : string       -- optional
  expiry         : uint256
  isTest         : bool

Global state:
  reservedNames  : mapping(string => bool)
  testNFT        : address
  registrationLimit : uint8     -- 5
  testLimit      : uint8        -- 5

There must be maps to track names by owner, but specific contract design should be based on ENS.

Name rules

ENS normalization (ENSIP-15) with additional restrictions enforced in dApp (registration) and resolvers (resolution). Contract follows ENS as-is.

Additional restrictions beyond ENSIP-15:

• No consecutive hyphens.
• No accented characters. Latin is a-z only (same as DNS LDH rule).
• Allowed scripts: Latin, Cyrillic, Arabic, Hebrew, Devanagari, Bengali, Thai, Greek, CJK, Hangul, Kana. Expandable as user base grows.

Registration flow

1. NFT check
2. Limit check (5 paid / 5 test)
3. commit(hash(name, owner, secret))
4. Wait (min 1 minute)
5. reveal(name, owner, secret) + ETH (zero for test)
6. Validate: well-formed, not taken, not reserved, fee covered
7. Store record

Pricing

Annual fees by name length:

Length	Fee
7+	base
6	4x
5	16x
4	64x
3	256x

Test names: free, expire after 3 months.

Renewal and expiry

Annual renewal. Grace period, then Dutch auction decaying to base price.

Updates

Owner can update links, admin address, admin email. Transfer follows ENS mechanics.

Reserved names

List for community channels (e.g., books, games, music, news):

• Not registrable by users
• Revenue shared with network

Retained ENS features

• Resolver pattern: registry maps name -> (owner, resolver). A SimpleX Resolver contract stores channel links, contact links, admin fields. Allows future extensibility without registry changes.
• Multicoin address records: BTC/ETH/XMR donation addresses per name. Subscribers see donation options from name resolution.
• Text records: generic key-value store for future metadata without contract upgrades.
• Reverse resolution: name lookup by address. Enables verification and discovery.
• Subdomain registrar: owner of acme.simplex can create support.acme.simplex, sales.acme.simplex without additional on-chain registration.

Removed ENS features

• Avatar/image records.
• .eth TLD and ENS name imports.
• DNS name registration (DNSSEC imports).

Governance

SimpleX Chat during testing and launch phases, migration to SimpleX Network Consortium.

Part 2: SMP protocol extension

New router role

data ServerRoles = ServerRoles
  { storage :: Bool,
    proxy :: Bool,
    names :: Bool
  }

Name-capable routers run an Ethereum light client.

Resolution protocol

Uses existing SMP proxy infrastructure. Client sends queries through a proxy, not directly to name servers.

Commands

Client -> Proxy -> Name Server:
  RSLV <namehash>

Name Server -> Proxy -> Client:
  NAME <name_record>
  ERR AUTH

Forwarded via PRXY/PFWD/RRES mechanism.

Two-operator resolution

Client -> Proxy A (Op 1) -> Name Server X (Op 1)
Client -> Proxy B (Op 2) -> Name Server Y (Op 2)

Both read same Ethereum state.

• Agree: trusted
• Disagree: warn, don't use
• One fails: retry with another server or show single result with reduced trust

Proxy sees client IP and session, but not query. Name server sees query, not client IP or session.

Name server implementation

1. Runs Ethereum light client (e.g., Helios) tracking SNRC
2. Receives RSLV via SMP proxy
3. Returns record from local state

State proofs can be added post-MVP.

Configuration

data NamesConfig = NamesConfig
  { ethereumEndpoint :: String,
    snrcAddress :: EthAddress,
    cacheSeconds :: Int
  }

Versioning

New SMP protocol version. Older routers/clients don't advertise the capability.

Default routers

Default router list updated to include name-capable routers.

Part 3: UI integration

Markdown

• #name or #name.simplex - native names (no dot = .simplex implied)
• #my-name or #my-name.simplex - hyphenated names
• #sub.name.simplex - subdomains (explicit TLD)
• #name.testing - test namespace
• Rendered as clickable resolve-and-connect links

CLI: # = local in group commands, global in /c and messages.

:name.simplex, :my-name.simplex - contact addresses (same namespace, different link type). MVP parser supports this syntax; resolution works; UI support is post-MVP.

Resolution flow

1. Normalize per ENSIP-15, compute namehash
2. RSLV to two name servers via two proxies
3. Compare results
4. First channel link -> short link resolution -> connection data
5. Present for joining

Search

#...simplex triggers resolution. Disable in "More privacy" settings.

Verification

On-chain link matches profile address = verified. Only name owner can set on-chain links.

• Manual: "Verify" button resolves and compares
• Auto: optional setting, resolves on profile open

Display

Show name and verification status. # is syntax, not part of the name.

Open questions

1. Contract upgrade mechanism: proxy pattern with timelock? Migration path for future Community Credits payment and domain name support.