About ISC's DLV Registry
DLV (DNSSEC Look-aside Validation) is an extension to the DNSSECbis protocol. It is designed to assist in early DNSSEC adoption by simplifying the configuration of recursive servers.
DLV provides an additional entry point (besides the root zone) from which to obtain DNSSEC validation information. Without DLV, in the absence of a fully signed path from root to a zone, users wishing to enable DNSSEC-aware resolvers would have to configure and maintain multiple trusted keys into their configuration.
Maintaining multiple trusted keys by hand is an unmanageable task. ISC DLV removes this need by serving as a trusted repository of entry points through which those keys can be securely retrieved by the resolver when it needs them.