; example.com zone 
  ; 
  $TTL 10 
  $ORIGIN example.com. 
  
@             100 IN SOA ns1.example.com. ( 
                  admin.example.com. 
                  2007112001 
                  100 
                  200 
                  604800 
                  100 
              ) 
  
                  NS      ns.example.com. 
ns1.example.com.  A       172.16.5.1 
a                 A       192.168.0.1 
b                 A       192.168.0.2 

$include Kexample.com.+005+18553.key ; ZSK
$include Kexample.com.+005+42209.key ; KSK