Port 3044: EndPoint Protocol — A Registered Ghost

What Port 3044 Is

Port 3044 sits in the registered ports range (1024–49151), the middle tier of the port number system. Registered ports are assigned by IANA to specific services upon request — unlike the well-known ports below 1024, no special operating system privileges are required to bind to them, and anyone can claim them with a successful application.

IANA's registry lists port 3044 as assigned to EndPoint Protocol (epp), registered to Stephen Cipolli at RADVISION — a Tel Aviv-based video conferencing and H.323 infrastructure company.¹

The Protocol Behind It

RADVISION's EndPoint Protocol was a proprietary signaling layer for their video conferencing endpoint products. Unlike standards-based protocols such as H.323 or SIP — which have detailed RFCs you can read and implement — RADVISION's EPP was never published as a public standard. There is no RFC. There is no open specification.

RADVISION was acquired by Avaya in 2012.² Their product lines were absorbed into the Avaya portfolio. The EndPoint Protocol, already obscure, became even less documented as the original organization dissolved.

The "epp" abbreviation IANA assigned to this port is also used for the Extensible Provisioning Protocol — the protocol domain registrars use to communicate with domain registries, which runs on port 700.³ Different protocol, same abbreviation. IANA's registry is a first-come, first-served system with limited namespace coordination.

What This Means in Practice

You are unlikely to encounter port 3044 in normal network traffic. The protocol it was registered for:

• Has no public specification
• Belongs to a product line from a company that was absorbed over a decade ago
• Was never widely deployed outside RADVISION's own ecosystem

If you see traffic on port 3044, it is almost certainly not RADVISION's EndPoint Protocol. It could be an application that chose this port arbitrarily, a development server, or something else entirely.

How to Check What's Using Port 3044

If you want to see what's listening on this port on your own machine:

macOS / Linux:

lsof -i :3044

Linux (alternative):

ss -tlnp | grep 3044

Windows:

netstat -ano | findstr :3044

To identify the process by PID (on Windows):

tasklist | findstr <PID>

Why Registered Ports Matter

The registered ports range exists to reduce collisions — if two applications both want to listen on port 8080, they conflict. Registration is how an application stakes a claim and signals to other developers: "don't use this."

But registration is not enforcement. Nothing prevents software from using port 3044 without permission, just as nothing stops someone from parking in a named space. The registry is a coordination mechanism, not a lock.

RADVISION's registration of port 3044 solved their problem in the early 2000s. Today, that registration is a historical artifact — a name on a door where no one works anymore.