# WHATPORT(56737)

## NAME

port 56737 — Unassigned (dynamic range) — Unregistered high port, scanned by default, claimed by nothing documented.

Protocol: TCP  
IANA registry

## DESCRIPTION

No IANA registration exists for 56737 and none can: RFC 6335 reserves this range for dynamic and private use. Nmap's nmap-services rates it "unknown" at 0.000228, and it sits directly beside 56738 in the same default top-1000 list. The SANS ISC service field is empty; the attributions on that page are unsourced visitor comments and should not be treated as fact. If it is open on your host, the process table is the only authority.

## EXPOSURE

**Expose with care.** Nothing known, nothing assumed. Name the process before you route traffic to it.

## CHECK

```sh
sudo lsof -nP -iTCP:56737 -sTCP:LISTEN
```

## SEE ALSO

- spec — [RFC 6335 — Dynamic Ports (49152-65535)](https://www.rfc-editor.org/rfc/rfc6335.html) (rfc-editor.org)
- iana — [IANA port registry — search 56737](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=56737) (iana.org)

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HTML: <https://whatport.net/56737/> · JSON: <https://whatport.net/56737.json> · full dataset: <https://whatport.net/ports.json>