Port 3477: eComm — A Registered Ghost

What Port 3477 Is

Port 3477 sits in the registered port range (1024–49151). These ports are assigned by IANA to specific services and applications — not reserved like the well-known ports below 1024, but formally documented so that software vendors can claim a number for their protocol.¹

In April 2002, IANA assigned port 3477 to something called eComm link port on both TCP and UDP, registered to Thomas Soerensen.² That's nearly everything that's known about it.

There is no RFC. No specification. No documentation of what "eComm" was — whether it was an e-commerce platform, a communication middleware product, or something else entirely from the era when slapping "e-" on a product name was considered a business strategy. Whatever it was, it didn't survive.

The Ghost Registration Problem

The IANA port registry contains hundreds of entries like this one: a name, a date in the early 2000s, and silence. The registration process at the time was relatively lightweight — submit a form, get a number. Many companies and individuals claimed ports for internal tools, commercial products, or protocols they intended to build, then never shipped anything significant or went out of business.

Port 3477 is registered in name. In practice, it behaves like an unassigned port. Nothing runs on it by default. No firewall rule-sets call it out. No network scanner signatures flag it.

What Might Actually Be Listening

If you see port 3477 active on a system today, it's almost certainly not eComm. It could be:

• A development server using it as an arbitrary high port
• A gaming application — port 3477 appears in some community documentation alongside PlayStation Network ports, though 3478 is the formally documented PSN port³
• Custom software that picked a number and got lucky (or unlucky)

The port means nothing on its own. The process behind it is what matters.

How to Check What's Using It

# macOS / Linux
sudo lsof -i :3477

# Linux (alternative)
ss -tlnp sport = :3477

# Windows
netstat -ano | findstr :3477
# Then check the PID:
tasklist | findstr <PID>

lsof will show you the process name, PID, and connection state. That's the only way to know what's actually there.

Why This Matters

The registered port range exists precisely to avoid chaos — software vendors agree on numbers so two applications don't fight over the same port. But a registration that outlasts the software it was meant to describe doesn't protect anyone. It just occupies a slot.

Port 3477 is a small lesson in how systems age: the registry endures, the software doesn't, and the gap between the two is filled by whatever happens to show up.