In previous articles, we explored communication between a Thread device and external (non-Thread) networks, primarily over TCP/HTTP using IP addresses and ports. However, in real-world applications, we rarely use raw IP addresses. Instead, we rely on hostnames — which are resolved to IP addresses using DNS (Domain Name System). Public DNS resolution (like Google’s 8.8.8.8) handles global domain names, typically configured at the OS or browser level. But for private, local networks — like those used in IoT and Thread-based deployments — we need a local DNS setup to resolve custom hostnames (e.