Attached please find the best six designs for the discussion (design 11, 12, 15, 16). Below is the description of Data center / DR site and office floor for your reference:
7/F of Data center is meet me room for connecting the fibre cables and core switches
There are 4 server rooms on 15/F to provide IT professional services (PC, printers etc)
5/F is DR site where is another building next to Data center
The bandwidth of all up links / cross links is 10G
Two 3750 are stack together with stacke cable
Assume that there is no costing issue among intra floor fibre cables
1. Which design is better? and why?
2. Some engineer suggest to remove the intra fibre cable (please find the "A" in blue color) between server rooms on 15/F. The network would be more stable. pls advise
It is the costing issue that cat 4500 may be considered to be core switch in this stage. The whole floor of 15/F would be rented as well. Once the traffic hits to certain level (or figure), the core switch would be upgraded to cat 6xxx serial.
If the intra fibre cables in the same floor are removed. which is the best design from the four design?
"Best" is subjective but i would go with 11.
If you remove the intra fibre cables then 16 becomes like 12. 15 is even worse.
The problem with 12 is that if the 4500 that you have connected the pair of 3750s to fails then that pair of 3750 switches are now isolated from the rest of the network. With 11 you don't have this problem because you have paths to both 4500 switches from each pair of 3750 switches.