mDNSResponder
mDNSResponder is the daemon that implements multicast DNS (mDNS) and DNS Service Discovery (DNS-SD), forming the local-network discovery and name resolution component of Apple's Bonjour technology. It enables devices on the same local area network to resolve hostnames ending in .local and to discover services advertised by other devices without a central DNS server.
Technically, mDNSResponder listens for mDNS queries over UDP on IPv4 multicast address 224.0.0.251 and IPv6 multicast
Platforms and usage: It is bundled with macOS and iOS as part of the Bonjour suite and
Open-source status: Apple has released mDNSResponder as open-source software under a permissive license, allowing developers to