Hybrid Unicast/Multicast DNS-Based Service Discovery

Document Type Replaced Internet-Draft (individual)
Author Stuart Cheshire 
Last updated 2014-07-26 (latest revision 2014-01-22)
Replaces draft-cheshire-mdnsext-hybrid
Replaced by RFC 8766
Stream (None)
Intended RFC status (None)
Expired & archived
pdf htmlized (tools) htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Replaced by draft-ietf-dnssd-hybrid
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


Performing DNS-Based Service Discovery using purely link-local Multicast DNS enables discovery of services that are on the local link, but not (without some kind of proxy or similar special support) of services that are outside the local link. Using a very large local link with thousands of hosts improves service discovery, but at the cost of large amounts of multicast traffic. Performing DNS-Based Service Discovery using purely Unicast DNS is more efficient, but requires configuration of DNS Update keys on the devices offering the services, which can be onerous for simple devices like printers and network cameras. Hence a compromise is needed, that provides easy service discovery without requiring either large amounts of multicast traffic or onerous configuration.


Stuart Cheshire (cheshire@apple.com)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)