DNS Anycast – What It Is And How It Works

Emilia

Speed and reliability are key factors for user satisfaction with online services. One of the fundamental elements of network functionality is the DNS (Domain Name System), which translates domain names into IP addresses. Anycast technology is an advanced way of distributing DNS services that significantly improves response times and availability.

How Does Anycast Work?

Anycast is a routing method that allows a single IP address to be assigned to multiple servers located in different parts of the world. When a DNS query is sent, the network directs it to the nearest Anycast server in terms of topology, minimizing latency and increasing response speed.

How It Works:

  • Unified IP Address: All Anycast servers use the same IP address, so users don’t need to know their physical location.
  • BGP Routing (Border Gateway Protocol): The BGP protocol informs routers in the network about the availability and location of Anycast servers, allowing traffic to be directed to the closest server.
  • Shortest Path: DNS queries are automatically directed to the server with the shortest routing path.

Importance of the First Byte (Time to First Byte)

Time to First Byte (TTFB) measures the delay between sending a request and receiving the first byte of data from the server. It’s a value given in milliseconds, measured from the time the request is sent until the user receives the first byte of data from the server. With Anycast technology and closer server proximity, TTFB is significantly reduced. Faster TTFB translates to a better user experience, faster page loading times, and more responsive web applications.

Impact of Long Distances on Latency

If a DNS server is far from the user, delays can accumulate, negatively impacting performance. Therefore, the geographic location of DNS servers is crucial. For example, if a user is in Singapore and sends a DNS request, it’s best if it’s handled by a local server in Singapore, ensuring minimal response time. If the server were in Europe, latency could reach 300-500 ms due to long distances and the time overhead of intercontinental connections.

In cases of intercontinental connections, such as between Australia and Europe, latency can reach 300-500 ms. This means slower page loads for the user and potential access issues. Deploying DNS servers worldwide minimizes these problems.

Why Is It Important to Have Servers on All Continents?

  • Reduced Latency: The closer the DNS server is to the user, the lower the latency.
  • Scalability: A larger number of servers across major continents allows for more users to be served without a performance drop.
  • Resilience to Failures: If one server goes down, queries are automatically routed to the next closest server.
  • Better Local Traffic Handling: Local users are served by local servers, which relieves international internet links.

Summary

Top hosting providers implement Anycast technology to ensure the highest service quality for their clients. By using geographically distributed servers, Anycast minimizes latency, increases performance, and enhances the overall user experience. At Smarthost, we have over 100 DNS servers worldwide. This ensures that every client, regardless of their location, connects to the nearest DNS server, guaranteeing minimal latency and maximum hosting performance.

Emilia
Latest posts by Emilia (see all)