I want to purchase two core switch and three access switch. All with redundancy.Attaching the diagram which will make you understand properly. My question is when to use SFT as an uplink between the core and access switch. I need the connectivity between core and access switch to be 1 GB. Can I uplink all of them in the normal ethernet port or do I need to uplink them with SFP. All the core and access switch will be in the same rack.