Overview of the Domain Name System (DNS)

The DNS is a technology that most IT managers don’t think much about; it works well and usually does not require much attention to support organizational objectives. As businesses increasingly rely on their web strategy, the DNS infrastructure deserves attention for many reasons, including:

  1. Increasing trend towards DDoS attacks against the DNS has raised awareness of weaknesses in traditional legacy DNS architecture that can easily be exploited.
  2. Increasing complexity of websites and web applications, along with sourcing of content from multiple different sites, has resulted in longer page load times. DNS latency, although typically low, is part of the total sum and optimizing your DNS infrastructure will enhance your users’ web experience.
  3. Understanding that, for many organizations, there are benefits to keeping local Canadian traffic within Canadian borders. This helps to improve information security, mitigate geographically sourced malicious attacks, and increase speed. DNS architectures can be configured to optimize regional traffic while serving global traffic.

To help demystify the DNS, this short primer provides information to help IT managers or technical decision makers re-familiarize themselves with the technology.

How does the Domain Name System (DNS) work?

The Domain Name System (DNS) provides the core backbone of the Internet by providing the map between easily-readable hostnames (i.e. www.cira.ca) and IP addresses (192.228.29.1) by way of resource records. It is essential to the operation of the Internet by enabling the use of logical, human-readable names for locations rather than complex IPv4 or IPv6 addresses. It additionally provides mappings to things like mail servers, SIP servers, redirects, digital signatures,
and more.

The DNS is a distributed database organized as a tree of interconnected nodes (server or server clusters) where each node is a partition of the database. Nodes are delegated to designated authorities and there can be only one authority for a node or group of nodes.