Zero Configuration Networking (Zeroconf) is a set of technologies that allow devices to automatically configure network settings and discover services without requiring any centralized servers. It uses IPv4 link-local addressing, Multicast DNS for name resolution, and DNS Service Discovery to find and list services on the network. Popular implementations of Zeroconf include Apple Bonjour, Avahi, and Mono.Zeroconf.

1. Zero Configuration
Networking
BY MURILLO GRUBLER

2. Zero Configuration Networking
 Service Discovery
 Zeroconf, what is it?
 Tecnology of Discovery
 IPv4LL
 Multicast DNS
 DNS-SD
 Main Implementations
 References
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3. Service Discovery
Service discovery aims to detect services on various devices on a
network of computers and allow them to use with minimal configuration.
Examples:
 Zero Configuration Networking
 UPnP
 SLP (Service Location Protocol)
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4. Zeroconf, what is it?
Created in 1999 by the group IETF (Internet Engineering Task Force), the
Zero Configuration Networking (Zeroconf) is a methodology and a special
set of technologies that enable the configuration of a network and
discovery of services in a simple way that an average user will not notice.
 Distribute IP addresses (without a Dynamic Host Configuration Protocol
(DHCP) server)
 Provide name resolution (without a Domain Name System (DNS) server)
 Find and list services (without a directory service)
 Distribute multicast IP addresses, if necessary (without a multicast server)
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5. DHCP (Dynamic Host Configuration Protocol)
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6. DNS (Domain Name Server)
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7. Tecnology of Discovery
 IPv4 Link-Local;
 Multicast DNS;
 DNS Service Discovery;
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8. IPv4 Link-Local Address
 There is no central server
 Each unit is responsible for choosing address
 The IPv4LL uses ARP (Address Resolution Protocol) to find a free IP
 This choice is made randomly from an address comprised of
169.254.1.0 to 169.254.254.255
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9. Multicast DNS
 There is no central server;
 The machine chooses its name;
 MDNS Responder;
 Queries to confirm a name and advertise services;
 Broadcast;
 MDNS uses the special multicast group 224.0.0.251;
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10. DNS Service Discovery
 With the DNS-SD, the computer will automatically search for services
on the network;
 DNS-SD works well with the MDNS but also works with the classic DNS;
 Messages for service discovery are of the same format queries;
 The queries are of type SRV, PTR, A and TXT;
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11. DNS Service Discovery - Types
 SRV: Contains name, service port, and host name;
 PTR: Is a pointer, stores the service type and service name;
 A: Stores the IP address of the service;
 TXT: It is used for additional service information;
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12. Main implementations
 Apple Bonjour;
 Avahi
 Mono.Zeroconf
 J-Share
 ZCIP
 JmDNS
 pyZeroConf
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13. Example – Mono.ZeroConfig
Main programn: Banshee
List with all definitions: http://www.dns-sd.org/ServiceTypes.html
 http: World Wide Web HTML-over-HTTP
 daap: Digital Audio Access Protocol (iTunes)
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14. References
 Oliveira F. A. Estudo sobre Redes Ad-Hoc Móveis com Suporte à
Descoberta de Serviços. Espirito Santo: 2011
 Siddiqui F; Zeadally S.; Kacem T.; Fowler S. Zero Configuration
Networking: Implementation, performance, and security; Computers
& Electrical Engineering: September 2012, Pages 1129–1145
 Trabalho zero. Available in http://www.linux-
magazine.com.br/article/trabalho_zero. Access on April 19, 2014
 Zeroconf. Available at http://www.zeroconf.org Access on April 18,
2014
 Multicast DNS. Available at http://www.multicastdns.org Access on
April 19, 2014
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