Break out notes: foil1------------------------ Mick Seamans: Multiple Spanning Tree Why do we need Spanning Trees? 1.Multiple links between 2 bridges 2.Multiple paths between 2 points in the network 3.Protection against outages caused by other people's trees 4.L2 firewalling Why not? Why not? 1.Multiple moels that are limited/not foolproof (temporary meltdowns. connectivity loss) 2.Over lapping VLANS reduce utility 3.Hard to understand (fully) foils------------------------ Questions: Q1.Are 1,2,3,4 (previous slice) the reasong why multiple spanning trees? Q2.We believe 1 & 3 in isolation are better/more easily dealt with by other techniques. Is this true? and therefore solving 2 & 4 are key. Q3.What are the current assumptions (competing sets of assumptions) for multiple trees. Q4.Are 1,2,3 the problems (we need some examples of each and all). Q5.What is the complexity we are willing to handle. Q6.What is a model for multiple spanning trees that isn't broken. What is broken - what are the criteria for success. Q7.What constraints (on topology, etc.) we will allow - what are the opportunities biven suitable constraints. Q8.How many VLANS per tree, hpw many trees in total. Q9.Does the "default" VLAN really exist - in the sense of passsing packets without a known VLAN relationship. Q10.Is MST just a very bad distance Vector protocol?