Port 3610: ECHONET — Japan's Smart Home Language

What Port 3610 Does

Port 3610 carries ECHONET and ECHONET Lite traffic — a communication protocol for smart home devices, energy management systems, and building automation equipment. If you're in Japan and your air conditioner talks to your solar panels, your smart meter coordinates with your storage battery, or your home energy management system knows how much power you're drawing — that conversation likely crosses port 3610.

IANA registered ECHONET on port 3610 for both TCP and UDP in September 2002.¹

How ECHONET Lite Works

ECHONET Lite operates at the application layer (OSI layers 5 and above), which means it's transport-agnostic by design. It runs over IP networks, both wired and wireless. The protocol uses two communication patterns:

Multicast announcements — A device broadcasts its state to the network. An air conditioner turns on and announces itself. Anyone listening can hear it.

Unicast control — A controller sends a targeted command to a specific device. Set the air conditioner to 22°C. The device responds with confirmation.

Every ECHONET Lite device is represented by one or more device objects, each with standardized properties. The specification defines objects for over 120 device types: air conditioners, solar generators, storage batteries, smart meters, heat-pump water heaters, sensors, lighting, and more.² A device from Mitsubishi and a device from Panasonic use the same object model. That interoperability is the point.

The History

The ECHONET Consortium was founded in 1997 by major Japanese electronics manufacturers, with backing from Japan's Ministry of Economy, Trade and Industry.³ The goal was practical: Japanese homes were filling with connected appliances from competing manufacturers, and they needed a common language.

The original ECHONET ran over various physical layers including infrared and power-line communication. ECHONET Lite, introduced in 2011, modernized the protocol for IP networks and became the version that matters today. The Ministry of Economy, Trade and Industry formally recommended ECHONET Lite as the standard interface for smart home systems — essentially making it the national standard.⁴

By fiscal year 2022, over 138.7 million ECHONET Lite-compliant products had shipped.²

This happened largely invisibly to the rest of the world. While Western markets debated Zigbee vs. Z-Wave and then Thread vs. Matter, Japan had already built and deployed a working ecosystem at scale.

ECHONET Lite vs. Matter

Matter (the newer cross-industry IoT standard) and ECHONET Lite solve similar problems. Both aim for multi-vendor interoperability in smart homes. Bridge solutions now exist to connect Matter devices to ECHONET Lite networks, which matters practically for Japan's installed base — you can't ask 138 million devices to upgrade.⁵

Outside Japan

ECHONET Lite is almost exclusively deployed in Japan. If you see port 3610 active on a device outside Japan, it's either:

• A device manufactured for the Japanese market
• Software that implements ECHONET Lite for niche automation purposes
• Something unrelated using the port informally

What's Listening on This Port

To check what's using port 3610 on your system:

# macOS / Linux
sudo lsof -i :3610

# Linux alternative
sudo ss -tulpn | grep 3610

# Windows
netstat -ano | findstr :3610

On most non-Japanese systems, nothing will be listening. On a Japanese home network with smart appliances, you may see your home energy management system (HEMS) communicating with connected devices.