Port 2979: H.263 Video Streaming — A Registered Port Nobody Uses

What This Port Is

Port 2979 is registered with IANA for H.263 Video Streaming on both TCP and UDP, assigned by Jauvane C. de Oliveira.¹

That registration almost certainly predates YouTube, before H.264 rewrote the rules on what video compression could be, before smartphones made video ubiquitous. It is a timestamp more than a specification.

What H.263 Was

H.263 is a video compression standard published by the ITU-T in 1995, designed specifically for low-bandwidth video — dial-up modems, ISDN lines, and early Internet connections that made streaming anything feel miraculous.²

It was the codec that made video conferencing systems like NetMeeting work when you had 56 kbps to spare. It succeeded at the thing it was built for: squeezing recognizable video through a straw.

But H.264/AVC arrived in 2003 and was simply better at everything. Then H.265/HEVC. Then AV1. Each generation made H.263 feel more like a curiosity. Today you would struggle to find software that streams H.263 video to port 2979. You would struggle to find software that streams H.263 video at all.

The Registered Port Problem

The IANA registered port range (1024–49151) contains thousands of ports like this one: formally claimed, historically coherent, practically abandoned.³ A researcher or developer registered the port for a legitimate project, the technology moved on, and the registry entry remains.

This is not a bug in the system. IANA does not reclaim ports the way domain registrars reclaim expired domains. The assignment is permanent. Port 2979 will say "H.263 Video Streaming" in the registry until the registry itself changes.

The practical consequence is that when you see traffic on port 2979, you cannot assume it is H.263 video. It is more likely something else entirely — a custom application, an ephemeral connection, or nothing meaningful.

What to Check If You See Traffic Here

If port 2979 shows up in your firewall logs or network monitoring, the honest answer is: it is probably not H.263 video. Check what is actually listening.

On Linux or macOS:

# See what process is bound to port 2979
sudo lsof -i :2979

# Or with ss
sudo ss -tlnp | grep 2979

On Windows:

# Find the process using port 2979
netstat -ano | findstr :2979

# Then look up the PID
tasklist | findstr <PID>

If nothing is listening, the traffic is likely transient — an outbound connection your machine made, not an open server. Check your firewall rules and running applications.