[c-nsp] Spanning-tree ports cost Formula

[A.L.M.Buxey at lboro.ac.uk]

Hi,
>    I think what he is asking for is how try the values were extracted

they are just default values for different interface types. 
I dont recall there being any formula (unlike eg OSPF/EIGRP calculations
on links). cant recall if its CCNA or CCNP SWITCH level stuff:

Spanning tree port cost (configurable on a per-interface basis—used on interfaces configured as Layer 2 access ports)
	
•10-Gigabit Ethernet: 2
•Gigabit Ethernet: 4
•Fast Ethernet: 19 


obviously this is of interest to those doing >10Gb links... 40Gb and 100Gb
only appear to have '1' to share ;-)

alan