Your solution is most likely fine if you are looking at the near term. Maybe you don't have any robust graphics/mapping, audio/visual-streaming, or VoIP requirements.
Quite possibly your business/operational applications won't require increased bandwidth and aren't expected to change over the next 3-5 years.
You might not even use an across-the-wire backup solution for devices located across a few floors.
You might issue policies that limit all desktop/printer systems to 100mb/Full duplex NICs, they certainly are getting cheaper to buy.
You might not even project having many new employees/customer additions in the near future.
There are many variables. But be conscious of the real goal---------- scalability, reliability and maintainability.
In my experiences I have never just put in enough infrastructure to meet opening day requirements. Copper and fiber installations have always been cheaper to implement early. They won't get cheaper down the line.
You could just go with your plan, but experience will prove different when 10GB comes to the smaller/mid-range switching platforms. Or your requirements mandate faster speeds.
We already are moving to 1Gb desktop NIC connections.
Things like redundant connections to core devices require pathways. Etherchannel alone
will give you some help if individual channel member ports/links fail, but it hardly qualifies as redundancy.
If you really apply the recommended Cisco Network Architecture, and apply it to your design, you may end up looking at dozens of "copper" etherchannel groups, where a few pairs of fiber would do the trick.
It really is all about pay-me-now, or pay-me-later when it comes to infrastructure design.
With 7 floors, which I'll assume are to be home-runned down to some Core/backbone environment, you'll have 28 etherchannel ports to terminate, with no real redundancy. If you added redundacy you're looking at 8 etherchannel ports per floor across 2 etherchannel groups which will need 28 ports across 2 core switches. What about STP, VTP, VLAN requirements?
You can achieve a better solution with a minimum 14 fiber ports, split 50/50 across a redundant pair of core switches (7 ports per switch)is much more reliable, easier to maintain and upgradable via relatively simple optic equipment upgrades.
It might seem expensive for opening day, but will prove a wise investment over the life of your network.
Lastly, SMF is cheaper to install than MMF, the optics are more expensive, but do drop in costs over the life of the technology.
Hope this helps.
