I reviewed the "Working with Active Directory" and was curious about the subnet part. I think Mike mentioned that each site that has the DC, you have to put in the subnets. My question is if you can use a summary address for it instead of listing all the subnets of that site?
My second question is if you go into the NTDS Settings and right click the server and select properties, you have a "Change Schedule" where you can replicate up to 4 times an hour. What is the difference between that setting and the IP "Defaultipsitelink" in the inter-site transports where you can change the replication there as well?