Port 3625: Volley — A Name Without a Service

What Port 3625 Is

Port 3625 sits in the registered port range — 1024 through 49151 — the territory IANA oversees for services that apply for an official assignment. Unlike the well-known ports below 1024, registered ports don't require root or administrator privileges to open. Any process can bind to 3625.

IANA assigned port 3625 to a service called Volley in October 2002, covering both TCP and UDP. That's where the paper trail ends. No RFC defines the Volley protocol. No public documentation describes what it does. No known software ships with it. The name was claimed, and then silence.

This isn't unusual. The registered port range contains thousands of names like this — services that were planned, partially built, or simply claimed speculatively and then abandoned. The registry is part directory, part archaeology.

If You See Port 3625 Open

Since no known legitimate software uses port 3625, finding it open on a system warrants a look. Check what process is actually listening:

On Linux or macOS:

# Show the process listening on port 3625
ss -tlnp | grep 3625
# or
lsof -i :3625

On Windows:

netstat -ano | findstr :3625
# Then look up the PID:
tasklist | findstr <PID>

The process name and path will tell you whether it's something you installed or something that shouldn't be there.

Why Unassigned Ports Matter

The 65,535 available ports are a shared resource. When a service claims a port number and then vanishes, it creates ambiguity. Any software that later wants to use port 3625 has to either:

• Register a different port
• Use it anyway and accept potential conflicts
• Rely on users to configure around collisions

This is why the registered port range can feel cluttered. IANA doesn't easily reclaim abandoned registrations, so ports like 3625 remain in limbo — officially named, practically vacant.

For most purposes, port 3625 is available. Just don't expect a ghost named Volley to answer.