Archive

Posts Tagged ‘UPnP’

Automatic hosts name resolution technics

January 19, 2011 Leave a comment

In this post, you will discover some well known hosts name resolution technics in a LAN. The purpose is to resolve hosts names without any manual configuration or using a third party solution. This feature is proposed by the zeroconf paradigm.

  • LLMNR (Link Local Multicast Name Resolution): Recently, Microsoft has developed this protocol and integrated it into Windows 2008/2008R2 and Windows Vista/7. The principle is to send multicast (not broadcast) name resolution requests to some machines (which have Networking Discovery feature activated).  This protocol is based on IPv6 but it can  theoretically use IPv4 and send requests to the 224.0.0.252 address.
  • mDNS (Multicast DNS): this protocol is proposed by Apple and aims to provide an automatic name resolution through a decentralized DNS . Each host host its special DNS table with the classical records. With mDNS, a host has the ability to choose any DNS suffix and and announce its new name through a multicast address. The name resolution requests are sent to  224.0.0.251 for IPv4 and ff02::fb for IPv6. mDNS is more used than LLMNR for its compatibility with DNS-SD (DNS based Service Discovery); another Apple product; which aims to facilitate Service Discovery and Announcement. Each host providing services advertises through DNS messages the different information. UPnP is another Microsoft solution but not so wellknown as DNS-SD which is supported by many hardware solutions, some linux distributions and so on.