Addresses are handed out in blocks. A block written 203.0.113.0/24 holds 256 addresses that share their first three numbers. Because one owner usually controls a whole block, a site that sees abuse from several addresses in it may act against all of them.
This is the weakness of buying a list of datacenter addresses from one block: they can all be blocked together. A rotating pool spreads requests across many blocks and many networks, which is one reason residential traffic is harder to filter.
With a rotating pool this is handled for you: one request after another usually leaves from different blocks. It matters most when you hold a session, because every request in that session comes from one address in one block.
Questions about subnet
What does /24 mean?
It is the size of a block: a /24 holds 256 addresses that share their first three numbers. A smaller number after the slash means a bigger block.
Why does it matter how many subnets a pool has?
A site that blocks a block removes every address in it at once. Requests spread across many blocks and networks lose far less to any single one.
Related terms
- ASN
- An ASN, or autonomous system number, identifies the network that owns a block of IP addresses, such as an internet provider or a hosting company.
- IP ban
- An IP ban is when a website refuses requests from a particular IP address, usually after seeing too many requests or behaviour it disliked.
- Proxy pool
- A proxy pool is the whole set of IP addresses a proxy service can send your requests through. Each request is given one address from it.
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