Systems, methods, and devices for resolving a network address include a Domain Name System (DNS) server configured to receive a request for a resource from a client device, determine a source IP address of the client device, and determine whether the source IP address is included in a source client list. In response to determining that the source IP address is not included in the source client list, the DNS server may determine whether a default view datastore includes a record for requested resource. If the default view datastore does not include a record for requested resource, the DNS server may determine whether the requested resource is included in the view datastore. If the requested resource is included in the view datastore, the DNS server may generate and send to the client device a response message that includes a SIPNOTDEFINED indication.