Subnet
A subnet is a group of neighboring IP addresses that belong to one network and differ in their last digits.
Addresses are handed out in blocks, not one by one. A block of 256 neighboring addresses is written as /24: they share the first three numbers, for example 203.0.113.x.
Websites look not only at a single address but also at the subnet. If similar activity comes from many addresses in one block, the whole block may be restricted at once.
So for independent accounts it matters that the addresses come from different subnets. A site will easily link ten proxies from the same block to each other.
In large pools of residential and mobile addresses this happens by itself: the addresses belong to different ISPs and cities.
FAQ
What does /24 mean?
It is a block of 256 neighboring addresses that share the first three numbers.
Why is it bad when proxies are from the same subnet?
The site sees that the addresses are neighbors and can link the accounts working from them or restrict the whole block at once.
Residential $1.59, mobile $2.50, datacenter $0.80 per GB
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