# WHATPORT(20828)

## NAME

port 20828 — Unassigned — Unassigned, unnamed, but scanned often enough to rank high in Nmap's frequency table.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA places 20828 in the unassigned block 20811-20998. Nmap lists it as 'unknown' yet with one of the higher open-frequencies among unnamed ports in this range, meaning internet-wide scans found it open on a measurable number of hosts without ever identifying what answered. No public protocol, product default, or RFC claims it. Treat an open 20828 as an unidentified application until a version scan says otherwise.

## EXPOSURE

**Expose with care.** Unnamed but commonly-open ports attract opportunistic probing. Fingerprint the listener and apply that service's rules.

## CHECK

```sh
nmap -Pn -sV -p 20828 --reason TARGET
```

## SEE ALSO

- iana — [IANA Service Name and Transport Protocol Port Number Registry](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml) (iana.org)
- source — [Nmap nmap-services frequency table](https://github.com/nmap/nmap/blob/master/nmap-services) (github.com)

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HTML: <https://whatport.net/20828/> · JSON: <https://whatport.net/20828.json> · full dataset: <https://whatport.net/ports.json>