On 3/18/2010 3:55 PM, Dale wrote: > I think avahi is a KDE thing. I don't really know what zeroconf is. If > I recall correctly, some package said it had to have that so I turned it > on. No clue what it is even after looking up the definition with euse. > May as well be Greek. ;-)
Zeroconf is a set of technologies that are supposed to generate a fully working IP network with no user or operator intervention. It includes three basic parts: link-local network config (e.g. IPv4LL), distribution hostname resolution (multicast DNS), and automatic service and device discovery (DNS service discovery). Used in the context of applications or services, you're usually talking specifically about the autodiscovery portion, which allows applications to find services and network devices automatically. It was primarily invented at Apple, who developed mDNS and DNS-SD, and is built into OS X as Bonjour. Avahi is just a free-software implementation of Bonjour (which was originally under the not-entirely-free Apple Public License), and from what I've read has practically overtaken Bonjour in terms of performance and features. Back onto the topic at hand: emerging cups with +zeroconf allows it to respond to service discovery requests. By default CUPS uses mDNSResponder, which is Apple's implementation; with +avahi is uses avahi instead. This means any Mac on your network will automatically see CUPS printers, as will any Linux client with avahi properly installed. Windows machines with iTunes or Safari installed probably have Bonjour as well, so they'd also benefit. On a side-note: CUPS 1.4 stopped supporting Avahi and only supports Apple's implementation, so the Gentoo devs have disabled zeroconf support completely until CUPS 1.5 (or whatever) brings back native Avahi support. --Mike