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one and two level subnetting

johnyb98

Good morning.

 

Suppose we have network 192.168.10.0 /24.

The host IP 192.168.10.1 /27 can be reached in both two following ways:

 

- one level subnetting : from 192.168.10.0 /24 to divide to 8 subnetworks. In this case, first host of first subnetwork is 192.168.10.1 /27

 

- two level subnetting : from 192.168.10.0 /24 to divide to 4 subnetworks. In this case, first subnetwork is 192.168.10.0 /26. If we divide this 192.168.10.0 /26 in to two subnetworks, first host of first subnetwork is 192.168.10.1 /27.

 

In both cases, the result is the same : host we reach is 192.168.10.1 /27. Subnetwork that this host belongs to is the same : 192.168.10.0 /27. But, is there any way to find out if it became from one-level or two-level subnetting?

 

Thank you for your time !

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I've never heard of one and two level subnetting but I assume you mean just taking a supernet and breaking it down multiple times. There isn't a way to determine how many times it's been broken up in the manner that you've described without information telling you that it's been done X number of times and you working backwards.

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Are you talking about tracking access or data across a network based on the subnet method implemented? If you want a way to trace connections and allow enough host for each subnet why not use IPv6 subnetting? It's incredibly easier. You'd have enough addresses and you wouldn't have this address conflict issue.

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7 hours ago, Lurick said:

I've never heard of one and two level subnetting but I assume you mean just taking a supernet and breaking it down multiple times. There isn't a way to determine how many times it's been broken up in the manner that you've described without information telling you that it's been done X number of times and you working backwards.

 

You are right. There is no "one or two level" subnetting term. It's just a term I have used. In this case, it would be better and more comprehensible to say one ore two step subnetting instead of one or two level subnetting. And my thoughts agree with you. If there is no other information telling you (or helping you decide) that it's been done x numbers of subnetting, there is no other way to find out how many times subnetting has taken place, and work backwards.

 

5 hours ago, Windows7ge said:

Are you talking about tracking access or data across a network based on the subnet method implemented? If you want a way to trace connections and allow enough host for each subnet why not use IPv6 subnetting? It's incredibly easier. You'd have enough addresses and you wouldn't have this address conflict issue.

I am just talking about if you had an exercise with just given these information and you are asked to find out how many steps of subnetting has been taken place. But, as Lurick said above, and I agree with him, without some other information telling you that it's been done X number of times, you cannot work backwards.

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10 minutes ago, johnyb98 said:

You are right. There is no "one or two level" subnetting term. It's just a term I have used. In this case, it would be better and more comprehensible to say one ore two step subnetting instead of one or two level subnetting.

Ah, that makes sense :)

Current Network Layout:

Current Build Log/PC:

Prior Build Log/PC:

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23 minutes ago, johnyb98 said:

I am just talking about if you had an exercise with just given these information and you are asked to find out how many steps of subnetting has been taken place. But, as Lurick said above, and I agree with him, without some other information telling you that it's been done X number of times, you cannot work backwards.

I would say I think I understand what you're asking but I'm afraid of being wrong. Though giving it a shot anyways if we're talking like on a paper exam then since both sets of subnets yield the same answer I see no way to tell which set the answer was derived from without more information. If you were told how many subnets were made, how many are needed, or how many host addresses need to be in each, then you could determine which is the answer.

 

Again this is my guess as to if it is what you're asking.

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There's really no difference between the two as you described.  Using a mask of a particular length only gives you so many binary possibilities.

 

/27 is pretty much just /27 whether your supernet is a /8 or a /26

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9 hours ago, Blake said:

Good work, you've just discovered CIDR or Classless Inter-Domain Routing.

More like overlapping vlsm? :')

I'm going to put a link to my PC specs which actually aren't my PC specs and I cry myself to sleep everyday so I can have these PC specs but I can't afford these PC specs so PC specs PC specs PC specs PC specs PC specs PC specs.

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On 8/5/2018 at 11:41 PM, Windows7ge said:

I would say I think I understand what you're asking but I'm afraid of being wrong. Though giving it a shot anyways if we're talking like on a paper exam then since both sets of subnets yield the same answer I see no way to tell which set the answer was derived from without more information. If you were told how many subnets were made, how many are needed, or how many host addresses need to be in each, then you could determine which is the answer.

 

Again this is my guess as to if it is what you're asking.

 

Yes, that is correct. My question was to figure out if you were given an e.g. /27 if it came from a /8 or a /15 or a /26 etc. Without any other information, you could not find out where it came from.

 

On 8/6/2018 at 12:09 AM, beersykins said:

There's really no difference between the two as you described.  Using a mask of a particular length only gives you so many binary possibilities.

 

/27 is pretty much just /27 whether your supernet is a /8 or a /26

 

You are right, beersykins.

 

Thanks for all the answers and the help !

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A few more help. . .

 

First octet of an IPv4 classful network is what specifies class the specific network belongs to. Subnet mask does not matter at all for placing it in a class. Subnet mask is only for subnetting/supernetting. e.g. 200.0.0.0 with 255.0.0.0 subnet mask is a class C network with 16,777,216 - 2 active hosts. Correct?

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