GE Campus network design

[PAUL CHEN]

Hi ,

Here is a design scenario:

Distribution 4605 4605

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L3 L3

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Core :--- 6509A sup720 --- ISL ---- sup720 6509A

--------------- L3 Etherchannel ------

| |

| |

L3 L3

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Distribution 4605 4605

I have 2 core switches connected to more than four 4605 distribution switches and I have routed links between them.

The distribution switches are in turn connected via 802.1Q trunks to 3550 access switches.

I have a ISL trunk between the 2 core sup 720 engines .

The links to the distribution switches all have a ospf cost of 10.

The L3 etherchannel between the core have a ospf cost of 5

Is this a good design in terms of load balancing and redundancy for a campus network ?

Any comments and input much appreciated

Thanks,

Paul

[pflunkert]

Hi Paul,

this is one possibility. For redundancy it would better if you have a etherchannel between the sups. Furthermore i would recommend DOt1q as trunk protocol. ISL is a Cisco standard. Also i would connect every cat 4500 to both cat6500. If the links a layer 3 or layer 2 links it's not so important. Every person can give you some advantages for both designs. On my view, i would do this:

When you have a new design include new ip addresses you can use Layer 3 links between the switches.

When you have an existing ip address range and you want implement new catalysts, sometimes it's not possible to use layer 3, because your vlans span over the whole campus. Then you can use RSTP as layer 2 protocol.

I hope this will help you.

Regards

Peter