What Is an Anycast Network and Why It Matters for Latency

Anycast is a routing strategy where the same IP address is advertised from multiple physical locations. When a user sends a packet to an anycast address, the internet routes it to the nearest location advertising that IP, based on BGP path metrics.

How it differs from unicast

With unicast, one IP maps to one server. Every user connects to the same machine regardless of distance. With anycast, the same IP resolves to different servers in different parts of the world. A user in Tokyo reaches a Tokyo node; a user in Frankfurt reaches a Frankfurt node.

Why it matters for latency

Latency is dominated by the speed of light and the number of network hops. Anycast minimizes both by routing traffic to the geographically closest PoP. A CDN or DDoS mitigation network with anycast across 50 PoPs gives every user sub-20ms proximity to an edge node.

Why it matters for DDoS absorption

Anycast naturally distributes a volumetric DDoS attack across all PoPs. A 500 Gbps attack hitting an anycast network with 50 PoPs becomes roughly 10 Gbps per location, which is far easier to absorb. Without anycast, all 500 Gbps land on one location.