15 December 2022
Anycast and Unicast are two different methods for routing network traffic in a network. Both methods are commonly used in the Domain Name System (DNS), which is the system that translates human-readable domain names (like google.com) into the numerical IP addresses that computers use to communicate with each other on the internet.
Unicast DNS is the traditional method for routing DNS traffic. In a Unicast DNS system, each DNS server is assigned a unique IP address, and client devices send DNS queries to a specific DNS server using that IP address. This method is simple and effective, but it has some limitations. For example, if the DNS server that a client device is trying to reach becomes unavailable, the client will not be able to resolve DNS queries until the server is back online.
Anycast DNS is a more advanced method for routing DNS traffic. In an Anycast DNS system, multiple DNS servers are configured with the same IP address, and client devices send DNS queries to that IP address. The network routing infrastructure then automatically directs the query to the nearest available DNS server, based on the location of the client and the availability of the servers. This allows for faster and more reliable DNS resolution because client devices can reach a DNS server even if the server they were originally trying to reach is unavailable.
Anycast DNS offers improved performance
Anycast DNS is considered to be a more efficient and resilient way of routing DNS traffic compared to Unicast DNS. It allows for faster DNS resolution and better availability, which can improve the performance and reliability of internet services. It also provides greater resilience against DNS-specific DDoS attacks due to its method of distributing traffic across its network.
Anycast routing distributes traffic across multiple DNS servers that are located in different regions. This allows the service to route traffic to the nearest available server, which helps to improve the performance of DNS resolution by reducing the latency and increasing the speed of response.
A good Anycast DNS network incorporates a load-balancing feature that automatically distributes traffic across multiple DNS servers, based on the availability and capacity of the servers. This help improves the performance of DNS services by ensuring that they are not overwhelmed by high volumes of traffic. Unicast can be overwhelmed by high volumes of traffic as it does not have the same routing capability of Anycast DNS.