simulating a large network

[Bash]

Hi,

I need to simulate a large network which interconnect all the computers in a university. Since it has a large number of nodes, could any one please tell me whether there is any limitation in ns-3.? 

Also, I have to duplicate one scenario for several times for example a switch connecting 10 nodes. Is there any easy method to do so?

Any help is most welcome :)

[pdbarnes]

Hello Bash,

We've run ~750K nodes on a 32GB machine with no problems. Since nodes have uint32_t ids, the code limits you to 4G nodes, but memory is usually the practical limitation.  (4G nodes would require ~200 TB).  

Peter

[Bash]

Hi Peter,

Thank you for your reply. Also I need to know whether there is a way to simulate the internet cloud?

Bash

[pdbarnes]

Lot's of ways, few of them good ;)

If you wan't something that looks like the Internet you'll have to read up the Internet topology literature and pick a representation that seems reasonable for your purposes.

If you're really interested in something else, but need a large network, you could use almost anything that preserves the effects you need.  

In one case we were only interested in the attachment of a site to the "internet."  We modeled the "internet" as a two level tree, with only ~100 leaf nodes to represent the servers on the "internet".  

In another case we wanted a small world topology with limited node degree, so we used a Watts-Strogatz graph.

[Francisco Eduardo Balart Sanchez]

Good day:

Actually i need to create a connected graph, come across with the Watts strogatz graph, is there a implementation for NS3 that can be shared.

Or is there a way to construct a connected graph using existing mobility models such as grid? (but look more randomly placed?)

Thanks in advance and best regards

[pdbarnes]

Watts-Strogatz is fairly easy to code; there isn’t anything already in ns-3 to help. Note that by itself W-S doesn’t give positions, just topology (links).

P

[Francisco Eduardo Balart Sanchez]

Thanks for the quick response Barnes :)

Correct, maybe i mis-phrased my question, my objective is to create a connected graph, since the Watts-Strogatz came up,
i wanted to know if there is a way to implemented in terms of x,y positions so it comply with such properties, at the end my objective is to have a connected graph, 

i did a thread for this specific item at: 

https://groups.google.com/d/topic/ns-3-users/b35oRkqc28s/discussion