Each Non-Root Switch now selects 1 Root Port by selecting the port with the Lowest Cost to the Root Bridge
Once the Internal Root Path is selected, all other paths to the Root Bridge are Blocked
In the example, the internal root path cost are:
S2 to Root Bridge on path 1 = 19
S2 to Root Bridge on path 2 = 38
Because path 1 has a lower overall path cost to the root bridge, it is the preferred path and F0/1 becomes the root
19 is the cost of a 100Mbps line from the last slide
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