# WHATPORT(90)

## NAME

port 90 — DNSIX Security Attribute Token Map — Registered to the DoD DNSIX security attribute token map; a legacy defense-network registration.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA assigns port 90 to `dnsix`, the DNSIX Security Attribute Token Map, from the US Department of Defense DNSIX (DoD Intelligence Information System Network Security for Information Exchange) work on labeled networking. It is not defined by an RFC and has no general-purpose implementation. Outside classified DoD deployments you will not meet it. An open 90 on an ordinary host is almost always a second web server or admin panel placed near 80.

## EXPOSURE

**Expose with care.** Whatever is listening is not DNSIX; identify it and apply that service's rules.

## CHECK

```sh
nc -vz TARGET 90
```

## 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)

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HTML: <https://whatport.net/90/> · JSON: <https://whatport.net/90.json> · full dataset: <https://whatport.net/ports.json>