Port 3089: ptk-alink — Registered, Forgotten

What Port 3089 Is

Port 3089 sits in the registered ports range (1024–49151). IANA officially assigns ports in this range to specific services — unlike the well-known ports below 1024 (HTTP, SSH, DNS), registered ports don't require root privileges to bind, and they carry less inherent authority.

IANA's registry lists port 3089 on both TCP and UDP as ptk-alink, short for ParaTek Agent Linking. ParaTek was a wireless network management company. Their agent-linking protocol is effectively extinct — the company was acquired years ago, the software is long past end-of-life, and virtually no one runs it. The registration remains in the IANA table the way an old nameplate stays on a door after the tenant leaves.

Known Unofficial Uses

Rainbow Six Vegas (and some related Ubisoft titles) uses UDP ports in the 3074–3174 range for multiplayer traffic, with 3089 falling inside that window. If you're gaming and see this port in use, that's the likely explanation. ¹

Beyond that, there's no prominent application that consistently claims 3089. It's one of thousands of registered-but-dormant ports.

What the Scanners Are Doing

SANS Internet Storm Center records steady scanning activity against port 3089 — dozens of probes daily from rotating IP addresses. ² This isn't a sign that something dangerous is happening specifically here. It's the Internet's background noise: automated bots sweeping port ranges looking for anything that responds. A port doesn't need to be famous to get swept.

If you're seeing these probes in your firewall logs, they're almost certainly opportunistic, not targeted.

How to Check What's Listening

macOS / Linux:

sudo lsof -i :3089

Linux (alternative):

ss -tulnp | grep 3089

Windows:

netstat -ano | findstr :3089

If nothing comes back, nothing is listening. That's the expected result on most systems.

Why This Port Matters

Unassigned and dormant registered ports like 3089 illustrate something real about how the Internet is built: the registry is a map, not a territory. Ports get claimed and then abandoned. Services get superseded. The namespace remains — 65,535 ports, most of them quiet most of the time.

The practical implication: if something unexpected is listening on port 3089 on your machine or network, you should find out what it is. Not because this port is dangerous, but because unexplained open ports on any number are worth understanding.