Name resolution using the Domain Name System (DNS) is integral to today's Internet. The resolution of a domain name is often dependent on namespace outside the control of the domain's owner. In this paper, the authors review the DNS protocol and several DNS server implementations. Based on their examination, they propose a formal model for analyzing the name dependencies inherent in DNS, and experimentally validate the model with actual domain names. Using their name dependency model they derive metrics to quantify the extent to which domain names affect other domain names. It is found that under certain conditions, more than half of the queries for a domain name are influenced by namespaces not expressly configured by administrators.