Port 1402: prm-sm-np — The Prospero ghost

Port 1402 sits in the registered ports range with an official assignment that almost nobody uses anymore. It's registered for prm-sm-np (Prospero Resource Manager - System Manager, Non-Privileged), a distributed computing protocol from the 1990s that has been functionally extinct for decades.

What Is the Registered Ports Range?

Port 1402 lives in the registered ports range (1024-49151). This is the middle tier of the port system:

• Well-known ports (0-1023): Reserved for core Internet services, tightly controlled
• Registered ports (1024-49151): Assigned by IANA to specific applications, but not as strictly enforced
• Dynamic/ephemeral ports (49152-65535): Unassigned, used temporarily by client applications

Registered ports are assigned through IANA's registration process, but the assignments are more flexible than well-known ports. Applications can request specific port numbers, and if nobody else is using them, they're granted. The catch: nothing actually enforces these assignments. Any application can listen on any registered port. The registry is more like a phonebook than a lock.

The Prospero Resource Manager

The Prospero Resource Manager (PRM) was developed at USC's Information Sciences Institute in the early 1990s.¹ Its purpose: distribute computing jobs across multiple machines connected by networks—local or wide-area.

Before cloud computing, before Kubernetes, before modern job schedulers, PRM tried to solve the problem of "I have this computation and multiple computers—how do I use them all?"

PRM split resource allocation across three components:

• System Manager (port 1402, prm-sm-np): Coordinated the overall system
• Job Manager: Handled individual computing jobs
• Node Manager (port 1403, prm-nm-np): Managed resources on individual machines

Port 1402 was the system manager's non-privileged port—the control channel for coordinating distributed processing.

Why You'll Never See This Port in Use

Prospero is dead. Not deprecated, not legacy—dead. The distributed computing problems it solved are now handled by modern orchestration systems, cloud platforms, and container schedulers. Nobody runs Prospero Resource Manager in 2026.

But the port registration remains. Port 1402 is officially assigned to prm-sm-np in IANA's registry, where it sits like an abandoned office with the nameplate still on the door.

What Actually Runs on Port 1402 Today

In practice, almost nothing. If you see traffic on port 1402, it's likely:

• Malware or unauthorized services: Attackers sometimes use obscure registered ports assuming they're unmonitored
• Misconfigurations: An application configured to use 1402 without knowing about the official assignment
• Custom internal applications: Organizations sometimes repurpose registered ports for internal services

Some sources claim IBM WebSphere Application Server uses port 1402 for SSL connections, but this isn't an official assignment—it's a common configuration choice.²

How to Check What's Listening on Port 1402

On Linux or macOS:

# See what's listening on port 1402
sudo lsof -i :1402

# Or using netstat
sudo netstat -tlnp | grep 1402

On Windows:

# Show all connections and listening ports
netstat -ano | findstr :1402

If something is listening, you'll see the process name and ID. In most cases, you'll see nothing—because nothing is there.

Why Unassigned or Dead Ports Matter

The port registry is full of ghosts like 1402. Protocols that were important in their time but are now obsolete. The registry preserves these assignments because:

1. Historical systems might still exist: Someone, somewhere, might still be running Prospero (unlikely, but possible)
2. Preventing conflicts: If IANA reassigned 1402 to a new protocol, it could conflict with any legacy Prospero systems
3. Documentation of Internet history: The registry is an archaeological record of what people were trying to build

But the practical reality: most registered ports are unused. The port system has 65,535 slots. We've only meaningfully filled a few hundred of them.

Port 1402 is officially spoken for. But in practice, it's empty space—a reminder that the Internet moves faster than its registries.

Related Ports

The Prospero suite claimed several nearby ports:

• Port 1403 (prm-nm-np): Prospero Resource Manager - Node Manager, Non-Privileged
• Port 1525: Prospero Directory Service

All equally unused today.