Port 1955: ABR-Secure Data — A Registered Ghost

What Port 1955 Is

Port 1955 sits in the registered ports range (1024–49151). These ports are assigned by IANA to specific services and applications — unlike the well-known ports below 1024 (which require root privileges and carry the Internet's most critical protocols), registered ports are claimed by individual vendors and developers for their software.

IANA's registry lists port 1955 as assigned to ABR-Secure Data (diskbridge) on both TCP and UDP, registered by someone named Graham Wooden.¹ The adjacent port 1954 is assigned to ABR-API (diskbridge) — the two appear to be part of the same product family.

The Honest Truth About This Port

Nobody talks about diskbridge. There is no meaningful public documentation, no open-source implementation, no community around it. The registration exists in the IANA database the way a company's name can persist in a state registry years after the business closed: technically real, practically invisible.

This is more common than you might expect. The registered ports range contains thousands of assignments made by companies and developers who registered a port, built (or planned to build) software around it, and then... didn't. The port number sits reserved in perpetuity, an artifact of the registration system's permanence.

Port 1955 isn't dangerous. It isn't interesting. It's a placeholder for something that never arrived.

If You See Traffic on This Port

If something on your network is using port 1955, it almost certainly isn't diskbridge. It's more likely:

• A custom application that chose this port arbitrarily
• Malware or a backdoor using an obscure port to avoid scrutiny
• A misconfigured service that ended up here by accident

When an unexpected port shows activity, the right response isn't to look up what it's "supposed" to be — it's to find out what's actually using it on your system.

How to Check What's Listening

On Linux/macOS:

# Show what process is listening on port 1955
sudo ss -tlnp sport = :1955

# Or with lsof
sudo lsof -i :1955

On Windows:

netstat -ano | findstr :1955

The output will show the process ID. From there, you can identify the executable — and decide whether it belongs there.

Why Unassigned (and Obscure) Ports Matter

The port system works because most software respects the registry. When your browser opens port 443, it knows HTTPS will answer. When your mail client connects to port 587, it knows SMTP submission will be there.

Ports like 1955 — technically assigned, practically unused — are the registry's dead weight. They're not harmful, but they illustrate something real: the IANA registry is a registry, not a guarantee. A port having a name doesn't mean that name is in use. A port being "unassigned" doesn't mean nothing runs there.

The gap between official assignment and actual deployment is wide, and port 1955 lives in that gap.