Which Network Service Is Also Known As Zero Configuration Networking?

Zero Configuration Networking (Zeroconf)

The IETF Zeroconf Working Grouping was chartered September 1999 and held its first official coming together at the 46^thursday IETF in Washington, D.C., in November 1999. By the time the Working Group completed its work on Dynamic Configuration of IPv4 Link-Local Addresses and wrapped up in July 2003, IPv4LL was implemented and shipping in Mac OS (9 & Ten), Microsoft Windows (98, ME, 2000, XP, 2003), in every network printer from every major printer vendor, and in many contrasted network devices from a variety of vendors. IPv4LL is available for Linux and for embedded operating systems. If you're making a networked device today, in that location's no alibi not to include IPv4 Link-Local Addressing.

The specification for IPv4 Link-Local Addressing is complete, but the piece of work to improve network ease-of-use (Nothing Configuration Networking) continues. That ways making it possible to accept two laptop computers, and connect them with a crossover Ethernet cable, and have them communicate usefully using IP, without needing a human being in a white lab coat to gear up it all up for you. Zeroconf is not limited to networks with only ii hosts, but as nosotros scale upward our technologies to larger networks, we always have to be sure we haven't forgotten the two-devices (and no DHCP server) case.

Historically, AppleTalk handled this very well. Dorsum in the 1980s if yous took a group of Macs and connected them together with LocalTalk cabling, yous had a working AppleTalk network, without any expert intervention, without needing to set upwardly special servers like a DHCP server or a DNS server. In the 1990s the aforementioned was truthful using Ethernet — if yous took a group of Macs and plugged them into an Ethernet hub, y'all had a working AppleTalk network, using AppleTalk-over-Ethernet. Now that information technology's common for computers to have IEEE 802.11 ("AirPort") networking congenital-in, you lot don't even need cables or a hub.

On Windows PCs, Microsoft NETBIOS and Novell IPX provided similar ease-of-use on small networks.

One major trouble with using IP for wide-surface area communication and AppleTalk, NETBIOS, or something else for local advice, was that it required awarding developers to support multiple different protocols with different semantics, conventions, and operational models. For example, a game developer writing a multi-player game would usually support IP to allow game-play beyond the Internet. However, a developer selling a game for $fifty doesn't have the technical support upkeep to provide telephone back up for people trying to configure their own "Net 10" IP network at home, so for the sake of ease-of-use, that developer too had to support AppleTalk (in the Macintosh version) and NETBIOS or IPX (in the Windows version) for people to play network games at dwelling house. Unfortunately, fifty-fifty after doing all that work the developers however hadn't actually solved their problem, because if someone with a Mac laptop wanted to play a network game with a friend with a Windows laptop, they were yet in the position of having to set up their own IP network, considering IP is the only cross-platform protocol their two machines had in common. It was clear that what the world needed was the ease-of-use of AppleTalk, applied to IP, the ubiquitous platform-agnostic communications protocol.

To accomplish AppleTalk ease-of-utilize in IP, there are iv main requirements:

Allocate addresses without a DHCP server (IPv4 Link-Local Addressing)
Interpret between names and IP addresses without a DNS server (Multicast DNS)
Find services, like printers, without a directory server (DNS Service Discovery)
Allocate IP Multicast addresses without a MADCAP server (future piece of work)

A final requirement is that the solutions in the four areas must coexist gracefully with larger configured networks. Zeroconf protocols MUST NOT cause harm to the network when a Zeroconf-capable car is connected to a large network.

It is important to understand that the purpose of Nada Configuration Networking is not solely to make current personal reckoner networking easier to use, though this is certainly a useful do good. The long-term goal of Zero Configuration Networking is to enable the cosmos of entirely new kinds of products that make use of IP networking, such every bit ubiquitous IP-based home automation and smart home products. In 1999, prior to the Zeroconf work, these products would simply not have been commercially feasible because of the inconvenience and support costs involved in educating customers near setting up, configuring, operating, and maintaining a network to allow those products to operate.

Documents

Zeroconf Requirements (typhoon-ietf-zeroconf-reqts-12.txt) defines the protocol requirements for nil configuration networking. This document was never published by the IETF, only the draft is made bachelor here for historical involvement.

Zeroconf Host Profile (typhoon-ietf-zeroconf-host-prof-01.txt) outlines which protocols are bachelor that could meet the requirements specified in the requirements document. In effect this draft is the embyonic form of a possible future RFC which could go an update to RFC 1122 (Host Requirements). This document was never published by the IETF, merely the draft is made available here for historical interest.

Autoconfiguration for IP Networking: Enabling Local Communication is a Zeroconf tutorial article past Erik Guttman, which appeared in the June 2001 issue of IEEE Internet Computing.

IPv4 Address Conflict Detection (RFC 5227) describes how a host can observe when another host on the same link is trying to apply the aforementioned IP address (a Bad Thing). This is the same mechanism used for Link-Local Addresses, but it is as useful and applicable no matter how an accost was configured, whether via manual entry by a human user, via information received from a DHCP server, or via any other source of configuration information.

Dynamic Configuration of IPv4 Link-Local Addresses (RFC 3927) specifies how IP hosts can assign addresses in the absenteeism of outside configuration information. That means assigning addresses without depending on information entered by a human user, and without depending on data obtained over the network from a special server, such as a DHCP server.

Zeroconf Multicast Address Allocation Protocol (ZMAAP) (draft-ietf-zeroconf-zmaap-02.txt) defines how IP hosts tin can allocate multicast addresses in the absence of exterior configuration information. This document was never published by the IETF, but the typhoon is fabricated available hither for historical interest.

An API for the Zeroconf Multicast Address Resource allotment Protocol (ZMAAP) (typhoon-ietf-zeroconf-zmaap-api-00.txt) is an informational draft extending RFC 2771 ("An Abstruse API for Multicast Address Allocation") to the Zeroconf environment. This document was never published by the IETF, but the draft is made available hither for historical interest.

Further Information

How hard is to implement IPv4LL? See Elementary IPv4 Link-Local Addressing

Uncomplicated IPv4LL implementation from Arthur van Hoff. For platforms that don't already have IPv4LL support built-in, there are various third-political party implementations, simply they tend to rely on existing libraries which may not be nowadays on all platforms. This version is but 380 lines, and is cocky-contained and doesn't depend on things similar libpcap or similar parcel capture libraries.

Multicast DNS provides name-to-accost translation and other DNS-like operations in the absence of a conventional DNS server.

DNS Service Discovery uses DNS SRV records to provide simple service discovery (network browsing), and works with both conventional unicast DNS and with multicast DNS.

WiSe-Zeroconf, an embedded Zeroconf stack.

Why should we adopt Zeroconf instead of UPnP? See How does Zeroconf compare with Viiv/DLNA/DHWG/UPnP?

May 2002: Apple announced their Nada Configuration Networking solution nether the production name Rendezvous. Apple is slap-up to leave AppleTalk backside and move to all-IP networking, and Rendezvous makes that possible. Rendezvous is now used by iChat, iTunes, iPhoto, Safari, file sharing, printing, and simply virtually every other piece of software that does networking on a Mac, including trusty old favorites like telnet, ssh, and ftp.

July 2004: The IETF Zeroconf Working Group concludes its work and wraps up.

Baronial 2004: Apple'due south Rendezvous for Windows Engineering Preview now available.

Apr 2005: Apple announces Bonjour, its new name for "Rendezvous 2", including broad-area service registration and browsing, extending Rendezvous beyond the local link, inbound NAT traversal (with compatible NAT gateways), new programming APIs for Java programmers, and all of the higher up for Windows also. The iFelix technical suport pages include a good "HowTo" page including four step-by-step screen shots on Printing from Windows XP using Bonjour. (Actually, the start screen shot is the "Welcome" screen, and the final is the "Congratulations printer gear up up is complete" screen, so actually at that place are only two existent steps — pick the printer, and verify that the Sorcerer picked the right driver.)

May 2005: The Asterisk Voice-Over-IP software PBX gets support for null-configuration customer setup using Zeroconf.

August 2005: Avahi released, a complete DNS-SD/mDNS implementation, licensed nether LGPL.

November 2005: Stuart Cheshire gave a Zeroconf talk to Google engineers, which was also recorded and made bachelor on Google Video.

Dec 2005: Nada Configuration Networking: The Definitive Guide by Daniel Steinberg and Stuart Cheshire, published by O'Reilly Media. There's a wealth of information on the Spider web about Zeroconf, perchance so much that it can be overwhelming. This volume gathers the essential material into a single convenient source, describing how the protocols work, and giving programming examples in C, Java, Python, and Ruby. Whether y'all're programming for Mac OS X, Windows, Linux, Solaris, FreeBSD (or whatever of the other supported Unix variants), or building a hardware device running an embedded Os like VxWorks, the cross-platform programming examples in this volume will show you lot what y'all demand to know to create a great Zeroconf product.

Jan 2006: Reckoner Linguistic communication Company releases new edition of its Calculator Desktop Encyclopedia, available both on CD and via the web, with entries for Zeroconf, Bonjour and Link-Local Address.

June 2006: With the help of Apple's Bonjour, setting up Windows XP to generate PDF from any Windows application that supports printing takes less than a minute and a half from startup. See the video on YouTube.

July 2006: More praise for the Bonjour for Windows Printer Setup Wizard, this time in an Ars Technica commodity nigh Parallels Desktop for Mac OS X.

March 2009: Fourth dimension to introduce the broader embedded systems customs to the technologies of Zero Configuration Networking: Stuart Cheshire speaks at the Embedded Systems Briefing.

June 2009: The Bonjour Sleep Proxy wakes your Mac automatically when you access it over the network.

October 2013: Presto from Collobos Software is an AirPrint-uniform IPP print server that also implements enough of a DNS server to answer unicast DNS-SD queries for the print services information technology is offering, making it a Wide-Area AirPrint Server. This ways that the printers it offers are visible to iOS AirPrint clients anywhere on a university or enterprise campus (and even remote clients connected via VPN), in dissimilarity to conventional multicast-but AirPrint services, which are visible only to clients on the same local link.

November 2019: At the 106^th IETF meeting in Singapore, November 2019, Stuart Cheshire presented an updated tutorial on Zip Configuration Networking, Multicast DNS, and Service Discovery.

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