# WHATPORT(5910)

## NAME

port 5910 — ats-atn (ICAO) / VNC display :10 in practice — Registered for air traffic services over the ATN; in the wild it is VNC display :10.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA registers 5910 as ats-atn, "Air Traffic Services applications using ATN", over TCP and UDP, with a separate SCTP registration named cm (Context Management). These are aeronautical telecommunication network services on private infrastructure. On a normal host, 5910 is 5900 plus display 10 — a hypervisor that has allocated ten guest consoles, or a machine with a long-lived set of VNC sessions.

## EXPOSURE

**Do not expose.** A double-digit VNC display usually means a virtualization host handing out guest consoles. That is an administrative surface and should be reachable only from the management network.

## CHECK

```sh
nc -w 3 TARGET 5910 | head -c 12; echo
```

## SEE ALSO

- iana — [IANA port registry — 5910 (ats-atn / cm)](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=5910) (iana.org)
- spec — [RFC 6143 — The Remote Framebuffer Protocol](https://datatracker.ietf.org/doc/html/rfc6143) (datatracker.ietf.org)

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HTML: <https://whatport.net/5910/> · JSON: <https://whatport.net/5910.json> · full dataset: <https://whatport.net/ports.json>