# WHATPORT(2020)

## NAME

port 2020 — xinupageserver — Registered to the Xinu teaching operating system; a historical name with no live protocol.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA registers 2020 as xinupageserver, from Xinu, Douglas Comer's teaching operating system at Purdue, whose remote page server used this port. It is a museum registration: no shipping software binds it today. An open 2020 is an application that took the port, or reverse telnet to line 20 on a Cisco terminal server.

## EXPOSURE

**Expose with care.** Unidentified listener: identify it before allowing it through a firewall.

## CHECK

```sh
nc -vz TARGET 2020
```

## SEE ALSO

- iana — [IANA port registry — 2020 (xinupageserver)](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=2020) (iana.org)

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HTML: <https://whatport.net/2020/> · JSON: <https://whatport.net/2020.json> · full dataset: <https://whatport.net/ports.json>