This document discusses planning for DNS infrastructure, including:
1. Creating a DNS server plan by determining capacity, location, roles, and security of DNS servers
2. Creating a DNS namespace plan by selecting an appropriate internal namespace
3. Creating a DNS zone plan by identifying zone requirements, types, and security and planning for additional DNS servers if the main server is overloaded
4. Creating a zone replication and delegation plan by selecting a replication methodology, securing replication, and planning for zone delegation to distribute load across servers