I found the following advantages of AD integrated DNS server
1. Zone File and Replication:
With AD integration,DNS server stores its database in Active directory instead of zone file like primary server which is at %WINROOT%\SYSTEM32\DNS.
The DNS zone transfer is handle by AD replication service so zone gets transfer by AD replication to all the domains.
So with this we do not require to make seperate replcation topology for DNS and AD.
2. Dynamice update:
All Active Directory integrated DNS zones are Primary zones (Multimaster). This offers a greater degree of fault tolerance when DNS clients need to dynamically update their records on a Dynamic DNS Server.
3. Secure updates:
Only AD integrated zones support secure dynamic updates, which let you control who can update DNS and reserve a particular name for a specific server to use.
