Port 356: Cloanto Net 1 — The Amiga Time Bridge

Port 356 carries the Cloanto Amiga Explorer protocol, connecting vintage Amiga computers from the 1980s to modern Windows PCs over TCP/IP. It's a network bridge across three decades of computing history.

What Runs on Port 356

Port 356 is officially assigned to Cloanto Net 1, a proprietary network protocol used by Amiga Explorer.¹ The service enables file transfers and system management between Commodore Amiga computers and modern Windows PCs.

When you connect an Amiga to your network and run Amiga Explorer, it establishes a TCP connection on port 356. The protocol handles bidirectional file transfers, converting between Amiga disk formats and modern file systems.²

Both TCP and UDP port 356 are reserved for this service, though TCP is the primary transport protocol for the file transfer operations.

The Amiga Preservation Story

In 2010, Michael Battilana—CEO of Cloanto Corporation—registered port 356 with IANA for the Cloanto Net 1 service.³ Cloanto had been developing Amiga software since the 1980s, creating productivity applications like Personal Paint and Personal Write for the original Amiga platform.⁴

By the 2000s, the Amiga had become a piece of computing history. Cloanto developed Amiga Forever, a legal emulation package that included ROM images and OS software for running Amiga emulators. Amiga Explorer was part of this preservation effort—a way to connect actual physical Amiga hardware to modern computers over a network.

The protocol was reverse-engineered by community members who monitored communications between the Windows version of Amiga Explorer and the Amiga side.⁵ Independent implementations like lxamiga and fuse-aexplorer emerged, allowing Linux users to connect to Amigas without needing Windows.

In 2019, Battilana acquired all Amiga Inc. intellectual property through C-A Acquisition Corp., cementing Cloanto's role as the official steward of Amiga heritage.⁶

How the Protocol Works

The Amiga Explorer protocol operates in two modes: serial connections and TCP/IP network connections. Port 356 is used for the network mode.

When establishing a connection:

1. The PC-side Amiga Explorer client connects to the Amiga's IP address on port 356
2. The Amiga-side daemon accepts the connection
3. File transfer commands are exchanged using Cloanto's proprietary protocol
4. Files are converted between Amiga Disk File format and standard file systems

The protocol handles the peculiarities of Amiga filesystems, including metadata that doesn't map cleanly to modern file systems.

Checking What's on Port 356

To see if something is listening on port 356:

# Linux/Mac
sudo lsof -i :356
netstat -an | grep 356

# Windows
netstat -ano | findstr :356

# Test connection to an Amiga
telnet 192.168.1.200 356

If you're running Amiga Explorer, you'll see connections like Connected to 192.168.1.200:356 successfully in your logs.

Security Considerations

Port 356 was historically flagged in some security databases as associated with malware.⁷ This doesn't mean the Cloanto protocol itself is malicious—rather, some Trojans in the past used port 356 opportunistically because it was in the well-known range but rarely used.

If you're not running Amiga Explorer or connecting to Amiga hardware, nothing should be listening on port 356. If you see unexpected activity on this port, investigate it.

Firewall Configuration: If you're using Amiga Explorer, you need to allow both TCP and UDP traffic on port 356 through your firewall for the Amiga and PC to communicate.

Why This Port Matters

Port 356 represents something important about the Internet's nervous system: not every port carries millions of connections per second. Some ports exist for small communities, for preservation efforts, for connecting obsolete hardware to the modern world.

The Amiga was a revolutionary computer in the 1980s, with graphics and multimedia capabilities that wouldn't become standard on PCs for another decade. By 2010, working Amiga hardware was increasingly rare. Port 356 is part of the infrastructure that keeps that history alive and accessible.

It's a reminder that the port system isn't just about the big protocols everyone uses. It's also about making space for specialized needs, for historical preservation, for communities that refuse to let their computing heritage disappear.

Related Ports

• Port 23: Telnet, the older remote access protocol that preceded secure alternatives
• Port 21: FTP, another file transfer protocol (though Amiga Explorer uses its own custom protocol)
• Port 548: Apple Filing Protocol (AFP), another platform-specific file sharing protocol