ISP servers?

Question

Computer networks

Why does an ISP need any servers?
What kind of servers do ISPs need? I'm not talking about the server for the database and the site, but about all sorts of billings, etc.

Answer 1

There are at least three directions for using server hardware: BSS (billing and all bindings), OSS (management systems and monitors) and service platforms (DNS, DHCP, radii ...). This is mandatory. Each direction is divided into a bunch of things. In addition, there is an active trend towards the virtualization of network equipment, virtualization of ATEs, mobile data transmission cores, routers, etc.
In addition, they are used for systems of non-technical office personnel (the same 1C, CRM, domain controllers, etc.)

Answer 2

That was.

Answer 3

For billing (oddly enough!).
Internal servers such as domain, mail for employees.
User database, technical support telephony server.
And so on.