By what principle will an ip address be allocated from a mobile operator?

Question

mobile connection

Interested in the following question - what is the scheme for issuing an ip address when connecting to the mobile Internet. That is, let's say the operator has a pool of addresses for city N. Next, the client connects, we give him ip_1. At the k-th disconnection, ip_k is returned. Is a subset of pool addresses used for a specific client, or is it just a random address chosen from a common one?

Answer 1

The operator has a BRAS on which a lot of external IP addresses are terminated, the client connects to the network and receives an internal IP, while a session is raised on the BRAS and either a random or the least loaded address is selected (no one canceled the limit on 65535-1024 ports / IP).

Answer 2

Good afternoon. In connection with the topic raised, I will describe one oddity.
I have a site that I administer and monitor the IP of logged in users for about a year now. They connect to me through the network of a mobile operator. For this operator, there are 1-2 matches of external IP within one day. Well, maximum 3 matches. Other days there is no IP match at all.
And just yesterday, the mobile operator immediately assigned 12 users from Minsk who visit my site the same IP.
Today there are 18 users, some I know personally - we work together, the operator assigned the same IP to them too. It never happened.
Something happened there that he assigns one external IP to everyone. Usually it is dynamic, it lasts a couple of hours in total.
Can anyone comment on this behavior of the mobile operator?

Answer 3

I think it's normal DHCP. Read about how DHCP allocates addresses.