DNS responses from simulated zones 

simulated root zone
looks much like the real root zone
same (refresh,retry,expiry,minimum) values in the SOA record
13 NS records ([a-m].root-servers.net) and 13 glue (A) records for those nameservers
TTLs for all records match the real root zone

159 top level domains (TLD) zones, each containing:
SOA record with values taken from real SOA records for its zone
some number of NS records, same number of glue (A) records (match real world, e.g. 13 NS+A records for .com, 8 NS+A records for .it)
values inside NS+A records, however, are fictitious; 24-hour TTLs for all NS and glue (A) records. 
delegations for subdomains