Anycast technology is a network architecture that allows end users to automatically route access requests to the optimal node by dynamically binding the same IP address to multiple service nodes around the world. Anycast technology has surpassed the traditional unicast (one-to-one) and multicast (one-to-many) modes, and implements a "one-to-nearest" intelligent routing mechanism through the BGP protocol. The following is an analysis of technical advantages, application practices and key considerations!

1. The core advantages of Anycast

1. Significantly reduce latency

User requests are automatically directed to the geographically closest node through BGP routing, shortening the transmission time caused by physical distance. For example, cloud service providers deploy 2800+ nodes worldwide, and the access latency from Asia to America has dropped from an average of 220ms to less than 120ms, a decrease of more than 40%. For high-sensitivity scenarios such as real-time game instructions and financial transactions, the first packet arrival time can be compressed to within 30ms.

2. Natural high availability and anti-attack capabilities

Node redundancy: When a node fails, the routing protocol automatically switches to the suboptimal node, and the service interruption time is less than 30 seconds. DDoS defense: Attack traffic is dispersed to multiple edge nodes for cleaning. The actual measurement shows that the service delay fluctuation is less than 5% under a 300Gbps attack, avoiding the collapse of a single point.

3. Simplified architecture and cost optimization

A single IP covers global services, and there is no need to configure independent IPs or DNS resolution strategies for different regions. Transnational transmission reuses cloud business intranet dedicated lines, which reduces the cost by 60% compared with public network dedicated lines, and is charged according to actual traffic to avoid idle waste.

2. Typical application scenarios and implementation practices

Global business acceleration

In game distribution, MOBA games deploy login servers in nodes such as Tokyo and Frankfurt through Anycast, and the global player delay is stable within 85ms, and the peak carrying capacity is increased by 3 times.

In live interaction, 4K live streaming relies on edge node transcoding, and the end-to-end delay is compressed to 800ms, with a jamming rate of less than 1%.

Critical infrastructure protection

DNS services such as public DNS (such as 8.8.8.8) use the Anycast architecture, with a single IP supporting tens of millions of queries and node failure-free switching. In financial transactions, cross-border payment platforms achieve transaction delays within 150ms in Hong Kong, London and New York, meeting the real-time requirements of financial supervision.

Enterprise collaboration and security services

After the OA system of a multinational enterprise is connected to Anycast, the speed of cross-continental file transfer increases by 400%;

Security cleaning service providers divert attack traffic to multiple entrances, and can digest T-level attacks without modifying DNS.

III. Key considerations for enterprise deployment

1. Protocol and state compatibility

Anycast is most suitable for stateless, UDP protocol services (such as DNS, NTP). If a TCP long connection is required (such as database access), middleware (such as HAProxy) is required to maintain session consistency to avoid connection interruption caused by routing switching.

2. Node health monitoring

The routing layer cannot perceive application layer failures. A service detection script needs to be deployed (example):

!/bin/bash
if ! pidof nginx; then
ifdown dummy0 revokes BGP routing announcements
fi

Ensures automatic isolation of faulty nodes when services are abnormal.

3. Compliance and billing traps

Regional restrictions: Some cloud vendors' Anycast EIPs do not accelerate cross-border traffic between mainland China and overseas.

Bandwidth peak: The upper limit of a single instance bandwidth is 2Gbps, and business negotiation is required for bandwidth exceeding 50Gbps.

Cost control: Prioritize the combination of "billing by traffic + reserved discount" to avoid idle resources caused by fixed bandwidth packages.

4. Network infrastructure dependence

The autonomous system (AS number) must support BGP broadcast. Small and medium-sized enterprises can use cloud vendor hosting services to lower the implementation threshold.

IV. Summary: Technology selection recommendations

Anycast has become a cornerstone technology for global enterprises to reduce latency, improve resilience, and simplify architecture. Its value is particularly prominent in real-time businesses such as games, finance, and live broadcasts. Enterprises should pay attention to the following when implementing:

Scenario matching prioritizes the deployment of stateless services such as DNS and API gateways; multi-cloud collaboration combines differentiated capabilities such as intelligent scheduling and security integration; cost monitoring sets bandwidth utilization alarms (such as >80% automatic expansion). In the future, as new protocols such as SRv6 become more popular, Anycast will be deeply integrated with edge computing and zero-trust security, further reconstructing the efficiency and boundaries of the global network architecture.