32 lines
1.5 KiB
Text
32 lines
1.5 KiB
Text
The mDNSResponder project is a component of Bonjour,
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Apple's ease-of-use IP networking initiative:
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<http://developer.apple.com/bonjour/>
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Apple's Bonjour software derives from the ongoing standardization
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work of the IETF Zero Configuration Networking Working Group:
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<http://zeroconf.org/>
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The Zeroconf Working Group has identified three requirements for Zero
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Configuration Networking:
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1. An IP address (even when there is no DHCP server to assign one)
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2. Name-to-address translation (even when there is no DNS server)
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3. Discovery of Services on the network (again, without infrastucture)
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Requirement 1 is met by self-assigned link-local addresses, as
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described in "Dynamic Configuration of IPv4 Link-Local Addresses"
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<http://files.zeroconf.org/draft-ietf-zeroconf-ipv4-linklocal.txt>
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Requirement 2 is met by sending DNS-like queries via Multicast (mDNS).
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Requirement 3 is met by DNS Service Dicsovery (DNS-SD).
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Self-assigned link-local address capability has been available since
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1998, when it first appeared in Windows '98 and in Mac OS 8.5.
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Implementations for other platforms also exist.
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The mDNSResponder project allows us to meet requirements 2 and 3.
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It provides the ability for the user to identify hosts using names
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instead of dotted-decimal IP addresses, even if the user doesn't have a
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conventional DNS server set up. It also provides the ability for the
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user to discover what services are being advertised on the network,
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without having to know about them in advance, or configure the machines.
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