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I have a Networking test in about 6 hours and I lost my notes on the subject matter and can't recall what the acronym was! Here's the problem case:

Given the address find the following subnets and appropriate 'subsubnets' (what's that called as well).

The graphic then goes on to show a diagram of many routers all connected and some routers have a switch connected with a number like 6000h meaning 6000 hosts. My task is to find the SUBsubnet that is needed to accomodate the ammount of hosts without wasting any IP addresses.

The thing I remember is that SUBsubnets have a different subnet mask '/28, /30' than the base father mask.

There is also the matter of connectivity, I have to make sure the entire network can ping whereever. They gave a class on the subject, but again, I can't remember the acronym. I think it was CDLRP or something like that. We're using Cisco's Packet Tracer, so any commands related to this would be great. Basically it's like this:

alt text

I hope all of this is making sense to you guys. Any help would be appreciated and some links to tutorials so I can brush up on them before the test.

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They're not called subsubnets, they're called subnets. is not considered a subnet, it's considered a network (it actually is a subnet of a larger network but from your perspective consider it a network, not a subnet). Any networks that you split off from the network are called subnets, because they are subnets of the network. – joeqwerty Aug 27 '10 at 12:29
Also, it's not called a supersubnet, it's called a supernet. You can also refer to it as supernetting, route aggregation, or route summarization. – joeqwerty Aug 27 '10 at 12:32
There's no sub-subnet; they're all just subnets. If you have a /24 subnet; you can divide that into several smaller subnets. I think the term supernet is leftover from the Classed IPs of yore; I wouldn't use it anymore, as others have said, it's a network or a subnet. – Chris S Aug 27 '10 at 12:33
Can you guys suggest a good tutorial for learning about supernetting? – Sergio Tapia Aug 27 '10 at 12:54
up vote 2 down vote accepted


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Yeah I think that's the answer to the a part of my question. Thanks! – Sergio Tapia Aug 27 '10 at 12:07

It's called CIDR and actually it means that you don't have classes in your network. Which can be translated as ... you can use any submask you want.

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Route summarization != CIDR. In fact a classful network is a summarization of its subnets.

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