Flat vs. Routed network

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Mar 2nd, 2009
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We have 3 buildings that are side by side. We have a fiber run between two buildings for a switch to switch connection (bridged), and we have a P2P T1 to the other location on a routed network. Ok, so we are going to try to phase out the T1 at the one location with wireless bridges. The wireless bridge can be in bridge mode or routed. I suggested to management that we stay with routed, but they want to flatten the network.

Do I have any good points that I can use that we shouldn't flatten this network? Is there a good reason to go flat, other than maybe ease of management?



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Overall Rating: 5 (2 ratings)
Jon Marshall Mon, 03/02/2009 - 07:51
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The main point i would make is that a flat network means a problem in one site can easily affect the other 2 sites. STP is the main issue i would have.

I would actually recommend you route between all buildings if at all possible although it depends on the vlan layout etc..


Mohamed Sobair Mon, 03/02/2009 - 08:04
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Here are 5 important reasons in order to go for Routed Network rather than Flat Network:-

1) IP Subnet Conservation.

2) Each Network is abroadcast domain, so it reduces the broadcast request across the Network.

3) Better Flexibility In filteration and provide better Security mechanism.

4) Reduces Bandwidth usage on the Network.

5) Better convergence and fast failure detection.




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