Bonjour is the current marketing name and the implementation of the [*Zeroconf*](http://www.zeroconf.org/) concepts. (Initially it used *Rendezvous* as the name.) These concepts provide for simple and intuitive recognition and configuration of certain networked computer devices, including workstations and printers.
Bonjour is the current marketing name and the implementation of the Zeroconf concepts. Zeroconf has 3 major goals:
- Allocate IP addresses without a DHCP server.
- Translate between host names and IP addresses without a DNS server.
- Discover services (like print providers) without a directory server like LDAP and make it easy to use them.
The complete technical Zeroconf concepts are specified in a series of RFCs, mainly:
- IPv4LL / rfc3927 for assigning Link-Local IP addresses without a DHCP server.
- mDNS / rfc6762 for multicast DNS to resolve hostnames without a central DNS server.
- DNS-SD / rfc6763 for DNS-based Service Discovery without a central directory server.
One of the principal architects of Zeroconf was Stuart Cheshire. After writing down his thoughts about how to implement Apple's original ease of use AppleTalk Name-Binding Protocol over TCP/IP networking got hired by Apple to help implement the Zeroconf concept for Mac devices. He then also was a principal author of the above linked RFC documents.
Apple's Bonjour implementation is also available for Windows and Linux (although on Linux there is also an independent implementation named Avahi) as Open Source under the Apache License v2.0.
IANA runs a service names and ports registry, where developers who wish to define and develop new service types for their systems can reserve names for them.