Understanding Bonjour and Peer to Peer networking

Apple’s Bonjour is a “zero configuration network” (Zeroconf) multicast Domain Naming System (mDNS) protocol used by Apple devices to enable the automatic and easy discovery of computers, devices, and services on IP networks. Bonjour (like other multicast services like Avahi and Microsoft’s UPnP) uses industry standard IP protocols to allow devices to automatically discover each other without the need to enter IP addresses or configure DNS servers. The elegance of this approach is that it brings simplicity and ease-of- use to the users of network devices and services. Eliminating the need to set up services such as Dynamic Host Configuration Protocol, DNS, and DNS Service Directory, Bonjour enables each device to continuously publish and discover services. By broadcasting Bonjour service messages, printers, servers, and other shared devices can advertise the services they offer. Client devices then monitor Bonjour advertisements and connect to the appropriate servers, as with any other service. The protocol also allows for a device to request services (Service Discovery) on the network as well as respond to incoming requests, which in some cases means a single device can be both a client and a server at the same time. The automatic discovery makes it easy for clients like iPads and Macbooks to easily use a printer using AirPrint or mirror a display to a projector using AirPlay