Port 2915: tksocket — Registered, then silence

Port 2915 is officially registered. On March 2, 2011, IANA received a request from someone named Dino Ciano, who claimed this port for a service called "tksocket" (TK Socket), covering both TCP and UDP. IANA recorded it. And then nothing happened.¹

No RFC. No open source project. No forum thread asking why something is listening on 2915. No firewall rule documentation. Nothing. The registration exists; the service, as far as the public Internet is concerned, does not.

This happens more than you might expect.

The Registered Ports Range

Port 2915 sits in the registered ports range, which runs from 1024 to 49151. This range works differently from the well-known ports below 1024.

Well-known ports (0–1023) are tightly controlled. HTTP gets 80. SSH gets 22. These are household names, maintained under IANA's strictest oversight.

Registered ports are looser. Any organization or individual can request one by submitting a form to IANA. The process isn't free-for-all — IANA does review submissions — but it's far from the rigorous standardization that governs the low-numbered ports. The result is a range that contains thousands of legitimate, widely-deployed services alongside hundreds of quiet registrations like this one: names attached to nothing anyone can find.

What "tksocket" Might Have Been

The name "tksocket" could suggest a connection to Tcl/Tk, the scripting language and GUI toolkit that has had networking capabilities for decades.² But this is speculation. Tcl/Tk has never used or claimed port 2915 in any official documentation, and the registration's assignee is an individual, not the Tcl development community.

The honest answer is: we don't know. The registration predates comprehensive archiving of minor software projects, and whatever tksocket was meant to be, it never made it to public documentation.

What to Do if You See Port 2915 Open

If you find port 2915 listening on a system, the registration tells you almost nothing useful. Treat it like any unexpected open port.

On Linux/macOS:

# See what process is listening on port 2915
ss -tlnp | grep 2915
# or
lsof -i :2915

On Windows:

netstat -ano | findstr :2915

The process ID will tell you what's actually running. From there, check whether that software belongs on your system and why it chose this port.

Why Ghost Registrations Matter

The registered ports range contains thousands of ports like 2915 — officially claimed, practically empty. This matters for a few reasons.

First, it means a registration is not a guarantee of active use. If you're trying to understand why something is running on a given port, the IANA registry is a starting point, not an answer.

Second, unoccupied registered ports are frequently used by software that needs a port and picks one informally — games, internal tools, custom services. Finding something on port 2915 doesn't mean you've found tksocket. It means someone's software picked a number, and this was it.

The registered ports range is less a directory of services and more a historical ledger of intentions.