Learning about network subsets - Overlapping addresses?
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Hello,
So first of all, I'm not certain which topic this subject belongs to so I apologize in advance.
I've been having a hard time finding a straight forward answer to my question so I would be grateful if you would give me advice on this matter.
I've been told that subnets divided in such a way that you segment part of the 32-bit network address to mean the network, and the other half to mean host address? IE: (<network><host>)
In this sense is it possible to have an IP address - say for instance 125.125.3.3 - in the subnet of 125.125.3.3/24 and another same address in the subnet of 125.125.3.3/16?'
If so, would these two addresses be mutually exclusive?Needless to say, networking isn't my profession, but I would still love to learn all about it. So, I would very much appreciate any advice or resources you would give me. :)
Thanks in advance,
Michael L.</host></network> -
No.
If a host in subnet 125.125.0.0/16 tried to contact a host in 125.125.3.3/24 it would think it is on its local subnet and not try to route it to the gateway.
Be careful to distinguish between routes and subnets.
If a router has the following two routes:
192.168.3.0/24 to gateway 10.10.10.1
192.168.0.0/16 to gateway 10.10.10.2That will work because the route with the longest mask will get the traffic.
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Subnetting and superscoping are ways to address groups of IP addresses instead of individually. It makes for less code which makes it faster. There are a few gotcha like every network has a network address and a broadcast address which can be overlaid on a larger address space. You just need to be aware of it.
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There's a nice CIDR/subnet calculator online that shows you exactly what addresses are part of a particular subnet and the details of the subnet in address/CIDR/netmask notations.