Port 1626: Shockwave — The ghost of the multimedia Web

Port 1626 is where the early Web learned to be multiplayer.

What Runs on Port 1626

Port 1626 was officially assigned by IANA to Shockwave—specifically, Macromedia's Shockwave Multiuser Server.¹ This server enabled real-time communication between Shockwave content (created with Macromedia Director) and multiple users simultaneously connected over the Internet.

The protocol supported:

• Multiplayer games
• Real-time chat rooms
• Shared whiteboards
• Live auctions
• Collaborative presentations
• "Connected entertainment" experiences

Both TCP and UDP protocols were registered for port 1626, allowing the server to handle both reliable messaging (TCP) and faster, connectionless communication (UDP) depending on the application's needs.

The History

In April 1999, Macromedia launched the Shockwave Multiuser Server licensing program.² This was before WebSockets. Before Socket.IO. Before most of the real-time Web infrastructure we take for granted today.

The server was designed to be installed on corporate intranets or Web servers, enabling Shockwave content to become collaborative and social. The initial release supported up to 1,000 simultaneous users and cost $1,000 per 100 simultaneous client licenses.

Port 1626 was chosen deliberately—Macromedia assigned this port "so that it would not conflict with other server applications running on the same computer."³ Every port number is a peace treaty. This one was negotiated in the registered ports range (1024-49151), the space where companies and developers request assignments from IANA.

The technology evolved:

• 1999: Shockwave Multiuser Server 1.0 launched
• 2000: Version 2.0 shipped with Director 8 Shockwave Studio
• 2001: Version 3.0 added server-side scripting, UDP networking, and support for 2,000 simultaneous users⁴

Then the Web moved on. Flash and Shockwave content gave way to HTML5. Real-time communication shifted to WebSockets. In February 2019, Adobe announced the discontinuation of Shockwave support, ending it officially on April 9, 2019.⁵

What This Port Carried

Every multiplayer Flash game you played in the early 2000s—every shared whiteboard, every multimedia chat room, every online auction that happened in real time through a browser—some of those connections flowed through port 1626.

This port carried the primitive ancestors of:

• Discord voice channels
• Google Docs collaboration
• Multiplayer browser games
• Real-time dashboards
• WebSocket-based chat apps

The technology is dead. The port is mostly silent now. But what happened here mattered. The early Web was static—pages you requested and read. Port 1626 was part of the shift toward a Web where people could be present together, in real time, doing things simultaneously.

Security Considerations

Shockwave Multiuser Server is discontinued and should not be running on any modern system. If you find port 1626 open on a network:

1. Verify what's listening — Use netstat, lsof, or ss to identify the process
2. Assume it's legacy software — Shockwave hasn't received security updates since 2019
3. Close it if unused — Discontinued software is a security liability

If you're running old infrastructure that still depends on Shockwave, you're living on borrowed time. Migrate to modern real-time communication protocols.

How to Check What's Using Port 1626

On Linux/Mac:

# See what's listening on port 1626
sudo lsof -i :1626

# Or use netstat
netstat -an | grep 1626

On Windows:

# Check if port 1626 is in use
netstat -ano | findstr :1626

If something is listening, the output will show the process ID. You can then identify the application and decide whether it should be running.

The Registered Ports Range

Port 1626 sits in the registered ports range (1024-49151). This is the middle ground in the port number system:

• Well-known ports (0-1023): Reserved for fundamental Internet services like HTTP (80), HTTPS (443), DNS (53)
• Registered ports (1024-49151): Assigned by IANA to specific applications upon request—like Shockwave claiming 1626
• Dynamic/ephemeral ports (49152-65535): Used temporarily by client applications for outbound connections

When Macromedia requested port 1626 in the late 1990s, they were following the process outlined in RFC 6335.⁶ Companies submit applications to IANA describing their service, and if approved, they receive an official port assignment. That's why the IANA registry lists "Shockwave" as the assignee for port 1626, registered to Sarah Allen.

The assignment is permanent, even though the service is dead. Port 1626 is forever marked as Shockwave's territory, a monument to technology that no longer exists.

Why Unassigned Ports Matter

Most ports in the registered range are unassigned. They're waiting. If you build a protocol that needs a port number, you can request one from IANA. The assignment prevents conflicts—it ensures that when your software says "connect to port X," there's no ambiguity about what should be listening.

But assignments also create archaeological records. Port 1626 tells a story. Someone built something, requested a number, launched it into the world. That service might thrive for decades or disappear within years. The port number remains, a marker of what once mattered enough to claim a piece of the Internet's namespace.

Related Ports

Other multimedia and collaboration ports from the same era:

• Port 1755 (TCP/UDP): Microsoft Media Services (MMS) — Windows Media streaming protocol
• Port 1935 (TCP): RTMP (Real-Time Messaging Protocol) — Adobe's Flash video streaming
• Port 5060 (TCP/UDP): SIP (Session Initiation Protocol) — Voice over IP signaling

These ports represent the same historical moment—the late 1990s and early 2000s, when the Web was learning to stream, to communicate in real time, to be more than static documents.