Version 4.1 - 3.5 DNS
DNS is outlined in RFC 1035. Cisco's page on DNS Best Practices gives a good outline of the protocol.
Important points would be to know the terminology (and what it does):
* Resolver
* Recursion (The action taken when a DNS server is asked to query on behalf of a DNS resolver.)
* Authoritative Server
* Recursive Resolver
* FQDN
* RR (Resource Record)
* Zone
Know the difference between Recursive and Iterative Queries. [Iterative queries return a referral - recursive will find an answer or give an error.] Know the types of Resource Records: A records, AAAA records, MX records, etc. Pay particular attention to IPv6 record types like RRSIG and DNSKEY. Also check out SPF records - which are txt records that identify which mail servers are permitted to send email on behalf of your domain.
The Cisco page noted above outlines the type of DNS attacks:
+ DNS Cache Poisoning
+ DNS Amplification and Reflection Attacks
+ Resource Utilization Attacks
I'm not going to spend too much time on DNS itself - since some of it was covered in DNSSEC. Again, a background as a server admin installing, configuring and maintaining a DNS server (especially in an Active Directory Domain) is something that will definitely come in handy here. Also, the network team is often tasked to administer (control) the DNS records for some organizations. If you've done these type of tasks, just make sure you're up to date on the DNSSEC and IPv6 stuff and move on to the next topic.