Networking / Beginners

Top Level Domain Servers

Hostnames are presented in a hierarchical format. Each dot in a hostname indicates another level in the hierarchy. For example, www.ucsc.edu is the host www in the domain ucsc within the top level domain (TLD) edu. The final extension on any fully qualified hostname-the individual host with full domain-indicates the TLD. On the Internet, all fully qualified hostnames contain a TLD from a limited selection. The type of TLD usually determines to type of domain.

As with the root-level servers, TLD servers do not store individual hostnames. Instead, these servers maintain pointers to the official primary name servers for a domain. The primary name servers are the authoritative source for specific hostname resolution. The root and TLD servers provide the means for an arbitrary host on the Internet to identify a specific primary name server. RFC2240 defines three types of TLD servers: gTLD, ccTLD, and SLD.

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In this tutorial:

  1. Domain Name System (DNS)
  2. DNS Common Uses
  3. Hostname-to-Address Mapping
  4. Common Lookup Tools
  5. Naming Confusion Attack Vectors
  6. Dotted Names
  7. Name Formatting
  8. Exploited Anonymity
  9. Mail Servers
  10. Sender Policy Framework Overloading
  11. Domain Keys Overloading
  12. DNS Protocol
  13. Packet Information
  14. Simple DNS Server
  15. Distributed Architecture
  16. Top Level Domain Servers
  17. Generic Top Level Domain (gTLD)
  18. Secondary Level Domain (SLD)
  19. Primary and Secondary Servers
  20. Caching Servers
  21. DNS Management
  22. DNS Direct Risks
  23. DNS Performance versus Security
  24. DNS Cache Poisoning
  25. Corrupt DNS Packets
  26. DNS Domain Hijacking
  27. DNS Server Hijacking
  28. Dynamic DNS
  29. Similar Hostnames
  30. Domain Renewals
  31. Hostnames
  32. Zone Transfers
  33. Host Listing
  34. DNS Fields
  35. Mitgation Option
  36. Technical Threat Mitigation
  37. Social Threat Mitigation
  38. Defining Trusted Replies