Port 2867: esps-portal — Registered, but Silent

Port 2867 sits in an interesting limbo: officially assigned, practically invisible.

IANA's Service Name and Transport Protocol Port Number Registry lists port 2867 — both TCP and UDP — as belonging to a service called esps-portal, with one Nicholas Stowfis as the registered contact.¹ Beyond that entry, the public record goes quiet. No RFCs. No open-source implementations. No deployment guides. No traffic signatures. The port has a name and a registrant, and that's roughly where the story ends.

What Range This Port Belongs To

Port 2867 falls in the registered ports range: 1024 through 49151.

This range is managed by IANA. Anyone can apply to register a port number for a specific service — the process is documented, the assignments are public, and the intent is to prevent two different applications from unknowingly colliding on the same number. The registered range is looser than the well-known ports (0–1023), which require higher privileges to bind and carry the most recognizable services: HTTP on 80, HTTPS on 443, SSH on 22.

Registered ports don't require elevated privileges to bind. Any process running under a standard user account can open port 2867. This makes the range useful for application-layer services that want a consistent, predictable address without needing root access.

What esps-portal Might Mean

The name "esps-portal" suggests an enterprise service of some kind — "ESP" commonly abbreviates "Enterprise Service Platform," "Enterprise Service Provider," or similar constructions. HPCC Systems, a big-data computing platform, uses ESP as the name for its service layer, though their components don't appear to use port 2867.²

Without public documentation from the registrant, the actual function of esps-portal remains unknown. It may be proprietary software used internally, a project that never shipped, or a registration that simply predates the modern expectation of public documentation.

How to Check What's Listening on This Port

If you're seeing activity on port 2867 and want to know what's using it:

On Linux or macOS:

# Show which process is listening on port 2867
sudo ss -tlnp sport = :2867

# Or with lsof
sudo lsof -i :2867

On Windows:

netstat -ano | findstr :2867

Then match the PID to a process name via Task Manager or tasklist.

Activity on an unrecognized registered port isn't inherently suspicious — plenty of legitimate software claims arbitrary ports in this range. But it's worth knowing what you're running.

Why Registered-but-Silent Ports Matter

IANA's port registry is a coordination mechanism, not an enforcement system. It records intent, not reality. The registry contains thousands of assigned ports for services that never shipped, products that were discontinued, or projects that existed only long enough to file the paperwork.

These silent assignments still serve a purpose: they stake out territory. If esps-portal claimed port 2867 in the registry, other developers are less likely to use it for their own software — avoiding a collision if the original service ever does appear on a network.

The Internet's port space is finite. 65,535 ports, allocated across three tiers. Registered ports fill the middle tier, and many of them look exactly like port 2867: formally claimed, functionally absent, waiting for context that may never arrive.