Open ports on ISP's gateway?

Question

Information Security

There is a small regional provider. Apparently, he has only one ip address, through which users access the Internet. On the same ip address on port 80, the site of this provider on apache and a rather old version of php is running, plus another web port is open, which seems to be being tested (not for public access). Port 445 is still open, what is it used for? How safe is it in general, for the provider and for the subscriber?
Also, the provider issues gray ip from the 192.168.xx range, how correct is this? I have never seen providers give out such addresses, there are conflicts and just confusion with the internal, home network.

Answer 1

about the port in the List of TCP and UDP ports it is written
445 / TCP,UDP MICROSOFT-DS - used in Microsoft Windows 2000 and later for direct TCP / IP access without using NetBIOS (for example, in Active Directory)
for which God knows the admin. and in passing hints that he is a burdock (but this is just my left look at the right heel). what is there in reality x3.
If the contract stipulates the provision of addresses 192.168.*** and the provision of access to the tyrnet using NAT or other technologies, then everything is ok. If configured correctly, it will work with certain restrictions (port forwarding, etc.)
Distribute addresses in the 10.*.*.* range on your home network, there are several more ranges of gray ip addresses recommended for local networks.

Answer 2

This is not a regional provider, it is a "local two quarters" level provider :) Saving on everything, including the admin. Port 445 is the Microsoft network. If he has it open at the gateway - burdock, Che. Waiting for his Mitnick. It's not safe for him at all :)
Selecting IP from the gray range - well, this is a typical practice for such providers. It is not prohibited by law if it is written in the contract.