# WHATPORT(9943)

## NAME

port 9943 — Unassigned — Unregistered with IANA; nothing well-known claims it, despite sitting next to Substrate's 9944.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA lists no assignment for 9943, and Nmap's service database calls it unknown, open on about 0.03% of scanned hosts. Its neighbour 9944 is the Substrate/Polkadot JSON-RPC default, but that does not extend to 9943 — no published project defaults here. Treat anything listening as a custom or ad-hoc service and identify it by banner rather than by number.

## EXPOSURE

**Expose with care.** No registration means no assumptions. Determine what the listener actually is, and whether it authenticates, before exposing it.

## CHECK

```sh
nmap -sV -p 9943 TARGET
```

## SEE ALSO

- iana — [IANA port registry — 9943 (no assignment)](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=9943) (iana.org)
- source — [nmap-services — Nmap's port frequency database](https://github.com/nmap/nmap/blob/master/nmap-services) (github.com)

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HTML: <https://whatport.net/9943/> · JSON: <https://whatport.net/9943.json> · full dataset: <https://whatport.net/ports.json>