updated 11:10 pm EST, Thu November 8, 2012
Proposal given to form a governing body for mDNS, ZeroConf
During a meeting of the Internet Engineering Task Force (IETF) in Atlanta, GA this week, Apple engineer Stuart Cheshire has proposed extending existing multicast DNS -- and by association Apple's Bonjour technology -- to better handle more complex network setups. The proposal is in response from complaints from colleges and universities regarding the networking protocol requesting that it function better with less bandwidth consumed on college campuses and other enterprise networks.
Bonjour, mDNS and Zeroconf -- the latter of which Cheshire invented -- are the core technologies that enable Macs to connect to most peripherals effortlessly, AirPrint to function from iPads to wireless printers, and AirPlay's streaming video from iOS devices to Apple TV units. As designed, the protocol is designed to work over a single router and associated network subnet. Hooks have existed since OSX Tiger for Bonjour to allow for wide-area service discovery, but it requires specific configuration of NAT-PMP on most Internet-facing network hardware, and construction of routing tables on larger enterprise networks.
Bonjour, as with other older Apple technologies like AppleTalk, is "chatty" (though less so than most older protocols), and can generate a lot of unrelated traffic on large networks. Additionally, multicast data from hundreds if not thousands of devices on college campuses can inundate network stacks from broadcast services like network printing and file sharing.
"Every network printer uses Bonjour. TiVo, home video recorders, and cameras use it. [Apple's] iPads and iPhones use it, and we are starting to get a lot of demand from customers concerned that they won't be able to print from iPads to a printer in the next building," Cheshire told Network World in an interview about his meeting with the IETF.
Representatives from Cisco, CheckPoint, and IBM support the measure proposed by Cheshire to improve the technology. A draft proposal has been floated to create a working group within the IETF to deal with the issue. "There's a recognition of the problem and a willingness to work on it," IBM engineer Thomas Narten declared.