# WHATPORT(306)

## NAME

port 306 — Unassigned — Unassigned by IANA; anything listening is a local or vendor-specific choice.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA has no registration for 306, and no public protocol claims it. Nmap lists it as "unknown" while still including it in wide scans because a measurable share of hosts answer, which usually points at embedded devices or a niche product rather than anything standardised. Do not read a service into the number — there is not one to read. The only honest answer is the registration status plus a service probe.

## EXPOSURE

**Expose with care.** No registered protocol means no assumption of authentication or encryption; probe it and treat it as untrusted until identified.

## CHECK

```sh
nmap -sV -p 306 TARGET
```

## SEE ALSO

- iana — [IANA Service Name and Transport Protocol Port Number Registry — 306](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=306) (iana.org)

---

HTML: <https://whatport.net/306/> · JSON: <https://whatport.net/306.json> · full dataset: <https://whatport.net/ports.json>