Unbound is designed as a set of modular components, so that also
DNSSEC (secure DNS) validation and stub-resolvers (that do not run as
a server, but are linked into an application) are easily possible.

Goals:
    * A validating recursive DNS resolver.
    * Code diversity in the DNS resolver monoculture.
    * Drop-in replacement for BIND apart from config.
    * DNSSEC support.
    * Fully RFC compliant.
    * High performance, even with validation enabled.
    * Used as: stub resolver, full caching name server, resolver library.
    * Elegant design of validator, resolver, cache modules.
          o provide the ability to pick and choose modules.
    * Robust.
    * In C, open source: The BSD license.
    * Smallest as possible component that does the job.
    * Stub-zones can be configured (local data or AS112 zones).

Non-goals:
    * An authoritative name server.
    * Too many Features.