Anycast
One IP, advertised from many locations; routing picks the nearest one.
Origin
RFC 1546 (1993) coined IP anycast. The 2002 K-root DNS server deployment was an early operational milestone. Cloudflare's 2010 launch made commercial anycast networks mainstream.
Where it shows up in production
- DNS root servers All 13 root letters are anycast — there are hundreds of physical instances worldwide answering for each letter.
- Cloudflare / AWS Global Accelerator / Fastly A single IP advertised from 300+ PoPs; the routing fabric picks the closest one.
On Semicolony
Sources & further reading
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