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This page presents the BETA version of DDec, CAIDA's public DNS Decoding database, public interface.

Many organizations encode geographic location, router type, and other information into their hostnames, for example LosAngeles and edge in By combing rules from multiple sources, DRoP and undns, DDec provides a single location for decoding DNS names.

Currently, DDec allows users to decode hostnames, find rules for individual domains, lookup encoding rules by name, or dump all the rule sets.

See also the documentation. Please email corrections/feedback to

Select one:      
Enter any text that contains one or more hostnames (e.g. a simple list, or the output of traceroute). DDec will decode each hostname as much as possible.
Display all DDec rulesets that contain rules that can be used to decode hostnames within a given domain.
Display a DDec ruleset in YAML format.
Ruleset name:  
Display all DDEC rulesets in YAML format.
Display patterns as:  

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