# WHATPORT(1717)

## NAME

port 1717 — fj-hdnet — A Fujitsu registration with no public protocol — rare in the wild.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA assigns 1717 (TCP and UDP) to "fj-hdnet", registered by Manabu Makino of Fujitsu. The registry provides only the name; there is no published specification and no broadly deployed product that binds it outside Fujitsu's own systems. If you see it, the answer is on the host, not in the registry.

## EXPOSURE

**Expose with care.** An unidentified vendor service is not something to expose by default — identify the owning process and its authentication before allowing it through a firewall.

## CHECK

```sh
nc -vz -w 3 TARGET 1717
```

## SEE ALSO

- iana — [IANA port registry — 1717](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=1717) (iana.org)

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HTML: <https://whatport.net/1717/> · JSON: <https://whatport.net/1717.json> · full dataset: <https://whatport.net/ports.json>