Avahi Vs. Bonjour
The Avahi project was originally started due to Apple's Zeroconf implementation, Bonjour, being licensed with the GPL incompatible Apple Public Source License. Since then, parts of Bonjour have been relicensed under the less controversial Apache License. However, Avahi had already become the de facto standard implementation of mDNS/DNS-SD on open-source operating systems such as Linux.
Avahi's performance is recognized as being similar to that of Bonjour, sometimes exceeding it, however Avahi was found to lose services when managing large numbers of requests simultaneously.
Stuart Cheshire (creator of Zeroconf) has stated in 2005 that Apple works with the Avahi team and is impressed with their progress; so much so that Avahi might "overtake Apple's implementation".
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