Port 1516: Virtual Places Audio — When web pages were chat rooms

Service name: vpad (Virtual Places Audio data)
Protocol: TCP/UDP
Port type: Registered (IANA-assigned)

Port 1516 carries audio data for Virtual Places, a chat application from the mid-1990s that turned every web page on the Internet into a potential chat room.

What Virtual Places Was

Imagine browsing CNN in 1997 and seeing avatars of other people floating on the page. You could chat with them, follow them to other websites, and collaborate in real-time—all while browsing. That was Virtual Places.¹

Created by Ubique, an Israeli company founded in 1994 by scientists from the Weizmann Institute, Virtual Places used a radical idea: the web browser itself was the chat interface. Avatars overlaid onto web pages. Real-time communication happening on top of the sites you were visiting.²

It was the Internet trying to be social before anyone knew what that meant.

The Port System

Port 1516 wasn't alone. Virtual Places used four ports:³

• Port 1516 (vpad) — Audio data
• Port 1517 (vpac) — Audio control
• Port 1518 (vpvd) — Video data
• Port 1519 (vpvc) — Video control

This separation of data and control channels was common in 1990s protocols. RTP does the same thing. One port carries the stream, another coordinates it.

The Brief Rise

Virtual Places found early success. AOL picked it up. Excite adopted it. At its peak, tens of thousands of people were chatting simultaneously on Excite using Virtual Places.⁴

AOL acquired Ubique in 1995. Then in 1998, IBM bought Ubique from AOL and integrated the technology into Sametime, their enterprise messaging platform.⁵ Port 1533 now carries what became of Virtual Places—IBM Sametime chat traffic.

Why It Failed

The idea was too weird. Chat didn't need to happen on top of web pages—it needed to happen alongside them. AIM figured that out. ICQ figured that out. Virtual Places was solving a problem that didn't exist.

By the early 2000s, Virtual Places was effectively dead. The ports remain registered with IANA, but nothing uses them anymore. Port 1516 is silent.

What This Port Teaches

Port 1516 is a reminder that not every protocol survives. IANA assigns port numbers, but assignment doesn't guarantee adoption. The registered ports range (1024-49151) is full of ghosts like this—services that seemed important enough to register but not important enough to endure.

The Internet has a long memory. Port 1516 is still officially assigned to Virtual Places Audio, even though Virtual Places has been gone for two decades. These registrations don't expire. They just become historical artifacts.

Checking for Activity

To see if anything is listening on port 1516:

# Check if port 1516 is in use
sudo lsof -i :1516

# Or use netstat
netstat -an | grep 1516

# Scan the port (on your own systems only)
nmap -p 1516 localhost

You won't find Virtual Places. But you might find something else—unassigned ports sometimes get repurposed by malware or unofficial applications.⁶ If something is listening on 1516, it's not what IANA intended.

Related Ports

• Port 1517 — Virtual Places Audio control (vpac)
• Port 1518 — Virtual Places Video data (vpvd)
• Port 1519 — Virtual Places Video control (vpvc)
• Port 1533 — IBM Sametime (what Virtual Places became)