Port 2720: wkars — A Name Without a Story

What Is Port 2720?

Port 2720 sits in the registered ports range (1024–49151), which covers ports that have been formally claimed through IANA — the Internet Assigned Numbers Authority, the body that coordinates global port assignments.

Unlike well-known ports (0–1023), registered ports don't require special operating system privileges to use. They're meant to be reserved for specific applications and services so that software can reliably find what it's looking for.

The Ghost Assignment

Port 2720 is technically not unassigned. IANA's registry lists it under the service name wkars, assigned to one Barry Shelton, over both TCP and UDP.¹

The description IANA provides for this service is: wkars.

That's it. A name that defines itself. No RFC. No company. No specification. No public documentation of any kind has ever surfaced explaining what wkars stands for or what problem it was meant to solve.

This is not uncommon in the registered port range. During certain periods, IANA accepted port registration requests with minimal requirements. The result is a graveyard of entries like this one — names without bodies, claims without purpose, ports that are officially occupied but functionally empty.

Is Anyone Actually Using It?

Almost certainly not for wkars — whatever that is. But ports with no active service don't stay quiet. Port 2720 gets scanned routinely by automated bots looking for open doors, and any software that happens to need an arbitrary high port might land here.

If port 2720 is open on your machine and you didn't put something there, it's worth investigating.

How to Check What's Listening

On Linux or macOS:

# Show what process has port 2720 open
sudo ss -tlnp | grep 2720
# or
sudo lsof -i :2720

On Windows:

netstat -ano | findstr :2720

The output will show the process ID (PID). Cross-reference it with Task Manager or ps aux to identify the program.

Why These Ports Matter

The registered port range was designed to prevent collisions — to ensure that when your database client connects to port 5432, it finds PostgreSQL, not something else. Ghost assignments like wkars represent the system working imperfectly. The port is claimed on paper but unclaimed in practice, which means any software could use it informally and there'd be no real conflict to speak of.

It's the digital equivalent of a deed for a plot of land that no one has ever visited, and the deed just says the land is called "wkars."