Networking connectivity overview

Important

This is the Azure Sphere (Legacy) documentation. Azure Sphere (Legacy) is retiring on 27 September 2027, and users must migrate to Azure Sphere (Integrated) by this time. Use the Version selector located above the TOC to view the Azure Sphere (Integrated) documentation.

The Azure Sphere OS currently supports two kinds of LAN network connectivity: Wi-Fi and Ethernet. Two pre-defined network interfaces are provided to support these methods: wlan0 for Wi-Fi and eth0 for Ethernet. The names eth0 and wlan0 are fixed for all MT3620 devices.

An Azure Sphere MT3620 device provides an 802.11 b/g/n Wi-Fi radio that operates at both 2.4GHz and 5GHz. Application libraries support networking. OS services manage network authentication and the network firewall for all outbound traffic. See Connect Azure Sphere to Wi-Fi for more information.

An Azure Sphere device requires an external Ethernet adapter to communicate over Ethernet. Connect Azure Sphere to Ethernet describes how to attach a supported Ethernet adapter and configure your device for communication.

Azure Sphere OS and services communicate with devices, Azure IoT Hub, and other services using various endpoints, ports, and protocols. The topic Azure sphere OS requirements lists the internet and public endpoints with which Azure Sphere devices must communicate for basic operation.

Azure Sphere devices rely on network connectivity to receive over-the-air OS and application updates. High-level applications can configure, use, and query the wireless communications subsystem, but they cannot program it directly.

You can configure an Azure Sphere device to connect to the Internet through a proxy server. When this feature is enabled all device traffic flows through the proxy. For more information, see Connect Azure Sphere through a proxy server.

Azure Sphere supports the MQTT messaging protocol for device provisioning and communication with Azure IoT Hub as well as non-Azure hosts. The MQTT project sample, in the Azure Sphere Gallery, demonstrates how to add MQTT support to an Azure Sphere project.

Azure Sphere applications can provide DHCP, SNTP, and other network services for external (non-Azure Sphere) devices on the network. See Use network services for details.

Networking problems can be difficult to diagnose and resolve. The topic Troubleshoot network problems provides some suggestions that may help to diagnose networking problems.