STP

From NetworkStuff

STP is an acronym for Spanning Tree Protocol, in relation to bridged or switched layer 2 networks. STP is used to automatically maintain a loop free topology in such networks where redundant links between devices are used. The original STP IEEE standard: 802.1D, published in 1990 has been revised twice, most recently in 2004.

Basic Data

IEEE Standard: [802.1D - 2004 incorporating RSTP, orginal standard published 1990

Layer Two Multicast Address: 01:80:C2:00:00:00

OSI Model Layer: Layer Two

Wikipedia Articles: http://en.wikipedia.org/wiki/Spanning_tree_protocol and http://en.wikipedia.org/wiki/IEEE_802.1D

STP Default Bridge Priority

Cisco: 32768

F5 BigIP: 61440

STP Default Path Cost

Data rate 	STP Cost
  4 Mbit/s 	250
 10 Mbit/s 	100
 16 Mbit/s 	62
 45 Mbit/s 	39
100 Mbit/s 	19
155 Mbit/s 	14
200 Mbit/s 	12
622 Mbit/s 	6
  1 Gbit/s 	4
  2 Gbit/s 	3
 10 Gbit/s 	2