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This question already has an answer here:

Suppose I have a network with IP address 192.168.10.1/16.
This network can hold up to 65536 machines, from 192.168.0.0 up to 192.168.255.255 (65534 machines without the network ID and broadcast address).

I have multiple questions :
Can I have a machine with the IP address 192.168.10.1 in this network?
Is the network with IP address 192.168.0.0/16 the same network as mine? If yes, it this true for any network with IP address 192.168.x.y/16?
Is my network ID address in this network (supposedly the address 192.168.0.0) the same as the network ID address in its subnetwork 192.168.10.1/17 (also supposedly the address 192.168.0.0)?

marked as duplicate by user36472, Ron Maupin ip Feb 8 at 13:39

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • Not at all, I know the answers to the question you linked. – J. Schmidt Feb 8 at 9:49
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    If you really understand what is explained in the answers to the above linked question, then you can easily answer your questions. I suggest studying the answers again. – Ron Maupin Feb 8 at 14:16
  • Well this is not really about the answer of the question linked as duplicate but about the method used to answer the question. You know, something about giving a fish or learning how to fish ;) – JFL Feb 8 at 14:16
  • The main problem here was I mistook a host IP address for a network IP address. The above linked question has nothing to do with this issue. – J. Schmidt Feb 8 at 15:09
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Suppose I have a network with IP address 192.168.10.1/16.

You don't. The /16 part means that to get the network address you only consider the 192.168. and whatever address is behind is part of the host address.

So 192.168.10.1/16 means: the host IP address 192.168.10.1 which is part of the 192.168.0.0/16 network.

So any address that begins with 192.168. and has a /16 prefix length is part of the same network, 192.168.0.0/16

Similarly 192.168.10.1/17 means: the host IP address 192.168.10.1 which belong to the 192.168.0.0/17 network.

Now we have two networks with the same numbers before the / and a different number after the /. What does that mean? It means one of the network is the subnet of the other: 192.168.0.0/17 is a subnet of 192.168.0.0/16

If we cut 192.168.0.0/16 in two subnets we got 192.168.0.0/17 and 192.168.128.0/17

Note that you cannot use a network and subnet(s) of this network at the same time. Either you use the full network as is or you use its subnet(s).

In this specific case this is still easy to manipulate those numbers in decimal form, but to understand what's going on and manipulate any prefix length / network address, you really have to do it in binary form. The answer linked in @Cown comment contains all the necessary information to perform those calculations.

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