intro.rst revision 303975
164562SgshapiroIntroduction 264562Sgshapiro=================================== 3261194Sgshapiro 464562Sgshapiro**Unbound** 564562Sgshapiro 664562Sgshapiro `Unbound`_ is an implementation of a DNS resolver, that performs caching and DNSSEC validation. 764562Sgshapiro Together with unbound, the libunbound library is provided. 864562Sgshapiro This library can be used to convert hostnames to ip addresses, and back, as well as obtain other information. 964562Sgshapiro Since the resolver allows to specify the class and type of a query (A record, NS, MX, ...), this library offers powerful resolving tool. 1064562Sgshapiro The library also performs public-key validation of results with DNSSEC. 1164562Sgshapiro 12132943Sgshapiro .. _Unbound: http://www.unbound.net/documentation 1364562Sgshapiro 1464562Sgshapiro**pyUnbound** 15266527Sgshapiro 1690792Sgshapiro The pyUnbound is an extension module for Python which provides an object-oriented interface to libunbound. 17159609Sgshapiro It is the first Python module which offers thread-safe caching resolver. 18159609Sgshapiro 1990792Sgshapiro The interface was designed with the emphasis on the simplicity of use. 2090792Sgshapiro There are two main classes :class:`unbound.ub_ctx` (a validation and resolution context) and :class:`unbound.ub_result` which contains the validation and resolution results. 2198121Sgshapiro The objects are thread-safe, and a context can be used in non-threaded as well as threaded environment. 2264562Sgshapiro Resolution can be performed blocking and non-blocking (i.e. asynchronous). 23159609Sgshapiro The asynchronous method returns from the call immediately, so that processing can go on, while the results become available later. 2498121Sgshapiro 2590792Sgshapiro**Features** 2664562Sgshapiro * customizable caching validation resolver for synchronous and asynchronous lookups 2764562Sgshapiro * easy to use object interface 2864562Sgshapiro * easy to integrate extension module 2990792Sgshapiro * designed for thread environment (i.e. thread-safe) 3064562Sgshapiro * allows define and customize of local zone and its RR's during the operation (i.e. without restart) 3190792Sgshapiro * includes encoding functions to simplify the results retrieval 3290792Sgshapiro * Internationalized domain name (`IDN`_) support 33157001Sgshapiro 34168515Sgshapiro .. _IDN: http://en.wikipedia.org/wiki/Internationalized_domain_name 35168515Sgshapiro 36168515Sgshapiro**Application area** 37168515Sgshapiro * DNS-based applications performing DNS lookups; the caching resolver can reduce overhead 38168515Sgshapiro * Applications where the validation of DNS records is required 3964562Sgshapiro * Great solution for customizable and dynamic DNS-based white/blacklists (spam rejection, connection rejection, ...) using the dynamic local zone manipulation 40