I am having a bit of a contemplation. Most things I read say to put a root bridge (per VLAN) as the Core Switch. I know most, if not all, the configurations about spanning-tree and root bridges and the election process. My question is would it be better to put a VLAN's root bridge closer to where the actual computers need to go. For example, if my company hosts a First Person Shooter fight and all they need to do is connect to a "host" machine on lets say a Distribution layer switch without ever crossing to the core, would it make sense to put the root bridge for that VLAN on the "Distribution" switch? Also I am confused about the concpt of a root bridge. Does all traffic "HAVE" to pass through the root bridge to go to its destination or is it just another mechanism that is implemented to better network performance? And if so how?
Any enlightenment would be a tremendous help.
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Root switch placement is optimally determined by trying to achieve the shortest number of hops for most of your traffic.
Suppose you had 5 switches connected in a ring. Let's assume most of your traffic was between switches 1 and 5. If you made switch 3 the root bridge, normally the link between 1 and 5 would block, so traffic between switches 1 and 5 would have to transit switches 2, 3 and 4. If, however, you made either switch 1 or 5 the root, then the traffic between these switches could use the directly connecting link.
In many topologies, the "core" is the central node in a hiearchal topology. As such, it's often the "best" root bridge.
With VLANs, and per-VLAN spanning tree, you can have different logical topologies. So, again with a physical ring, switch 3 might be the best root for one VLAN and switch 1 the best root for another VLAN.
When your underlying physical topology is partially meshed, not only can you design the optimal topology for certain transit traffic in "normal" (i.e. everything operating) but best alternative topology for device failures. This can get quite complex, which is also why dual hierarchal physical topologies are used with a primary and alternate root being on core bridges.