IP blocking stops traffic to particular server addresses, so a site stays unreachable even when its name is looked up correctly.
Explanation
Every server on the internet is reached through an IP address. A network that blocks an address, or a whole range, drops or resets packets going to it, so changing DNS settings does not help. The weakness is that addresses are shared. Large sites sit behind content networks and clouds whose addresses also serve many other customers. In our DomainScan scan of 38 popular sites on 5 October 2026, seven, including chatgpt.com, discord.com, x.com, signal.org and anyproxy.site itself, were on Cloudflare's network (AS13335), and six, including reddit.com and bbc.com, on Fastly's (AS54113). Blocking an address used by one of them risks cutting off its neighbours. Russia showed the cost in April 2018: chasing Telegram onto Amazon and Google cloud addresses, Roskomnadzor's blacklist reached about 20 million IP addresses and unrelated services failed, while Telegram kept working for many users. In February 2008 Pakistan Telecom tried to block YouTube by rerouting its addresses; the route leaked to the global internet and took YouTube offline worldwide for about two hours. Addresses also change, so block lists need constant upkeep.
In practice
Shared infrastructure is why IP blocking causes collateral damage. Our 5 October 2026 scan put 13 of 38 popular sites on just two networks, Cloudflare and Fastly. A web proxy changes which addresses your device contacts: only the proxy's. That helps when the destination's addresses are blocked, and fails if the network blocks the proxy's addresses instead.
Sources: Meduza - Russia's censor blocks millions of IP addresses chasing Telegram (17 Apr 2018) · RIPE NCC - YouTube hijacking case study (2008)
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