CGNAT
CGNAT is a technology where a carrier puts hundreds of subscribers online through one shared IP address.
There have long been too few free IPv4 addresses for everyone. Carriers solve this as follows: subscribers get internal addresses and go online through a small number of shared external ones.
As a result, a website sees the same address for hundreds of different people. It cannot tell them apart by IP alone.
This gives mobile proxies their main property: restricting such an address means affecting many ordinary subscribers, and sites are reluctant to do it.
For the same reason the carrier can change your external address at any moment: it is not assigned to you personally.
FAQ
Is my home internet behind CGNAT too?
Possibly: some home ISPs do this as well. But with mobile carriers it is almost always the case.
Why can't I hold an address for long because of CGNAT?
The carrier assigns the external address and can change it at any moment. It is not assigned to a specific subscriber.
Related terms
Residential $1.59, mobile $2.50, datacenter $0.80 per GB
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