Gray ip address, NAT and ftp accessible from the Internet?

Question

Computer networks

The situation - in the properties of the connection in the router I see the address 10.160.*.*/30. In the ip check service (2ip.ru) I see ip 176.59.*.* I call the provider and he tells me that my address is gray.
Questions:
1) Do I understand correctly that the provider provided the same 176.59.*.* address to several people and they are on the Internet with me under it at the same time?
2) Do I understand correctly that this all works through NAT, and the essence of NAT is that the provider's router assigns individual local addresses of the form 10.160.*.*/30 to all clients, and when it sends outgoing packets from them to the Internet, it appends to to these packets the ports assigned to each of the clients, so that later on these ports to navigate, to which of the clients to redirect incoming packets that will have the addresses of these ports?
3) If I suddenly want to do ftp on this gray IP, to the common address 176.59.*.* which many clients have at the same time, do I need to add the port number that the provider's router assigned for me as a separate client? For example, someone's account in the provider's router is listed with port 15678, which means that his ftp will be available at ftp://176.59.*.*:15678 ? How can I find out the port number? At the local address 10.160.*.*/30 in which 30 comes after the slash, is 30 the same port number?
4) 176.59.*.* is it a white address, which is the address of the provider's router, which, using NAT, redirects from clients to Internet packets?

Answer 1

1) yes
2) not really, rather no than yes
3) as a rule, providers do not forward ports at all to clients behind NAT. And /30 is a subnet, it has nothing to do with ports
4) like that, only this "router" is not much like a home router,
usually such problems are solved by the additional service "White IP" or "Static IP". It is technically important to receive incoming messages that there is both a white and a static IP at the same time, but providers often have confusion with terminology.
White IP - this is when the client is not behind NAT, but immediately enters the network with an external IP
Static IP - this is when it does not change for you during the entire period of using the Internet (desirable, but not a prerequisite)

Answer 2

1 .Yes. And maybe not a few, but hundreds of people :)
2. Yes, but only in the very, very general sense. There are many more mechanisms involved in NAT, and they are much more complex.
3. No. Misunderstanding what NAT is leads to false conclusions. There are no statically allocated ports, everything works dynamically. Theoretically, the provider can forward the port inside the network, but practically no one ever does this for clients. /30 is the subnet mask in CIDR format, in "normal" form it is 255.255.255.252
4. Yes

Answer 3

1) Do I understand correctly that the provider provided the same 176.59.*.* address to several people and they are on the Internet with me under it at the same time?

Yes.

2) Do I understand correctly that this all works through NAT, and the essence of NAT is that the provider's router assigns individual local addresses of the form 10.160.*.*/30 to all clients, and when it sends outgoing packets from them to the Internet, it appends to to these packets the ports assigned to each of the clients

Hands out local DHCP addresses. NAT is engaged in "proxying". When connecting from a gray address through NAT, a port is dynamically allocated on the router server for feedback, but this is not for the client, but for a specific session.

3) If I suddenly want to do ftp on this gray IP, to the common address 176.59.*.* which many clients have at the same time, I need to add the port number that the provider's router assigned

The port is dynamically assigned to each individual session, not to your computer. Therefore, it won't work. Technically, you can do port-forwarding and assign a static port, but your ISP most likely does not provide such a service.

4) 176.59.*.* is it a white address, which is the address of the provider's router, which, using NAT, redirects from clients to Internet packets?

Perhaps the provider is a little more complicated and there are more addresses. But in general, yes.