Date of Issue: 12-01-2023 Rate this Study Guide


ISIS Part II: Hierarchical Networks

by Peter Van Oene

Introduction
Hierarchy in ISIS
    Why do link state protocols impose such a structured hierarchy?
  Demystifying Levels and Areas
  The Backbone
Communicating IP Reachability
    Note
  LSPs and TLVs
    LSAs Vs. LSPs, or, should I say, TLVs
  The Tutorial Network
  Why defaults in L1, but not L2?
  IP Internal Reachability
    The Type 128 TLV
    Router Roles
    Flooding
  IP External Reachability
    The Type 130 TLV
    A note on LSP Flooding
    Router Roles
    Flooding
    A slight digression into the past and present use of IP Reachability TLVs
    A Note on Reality vs. RFC
Traffic Engineering
  Messing with Metrics
    Wide Metrics
  Dealing with Defaults
  Route Leaking
    Hint
  Internal Route Summarization
  Summarizing into the Backbone
  Summarizing While Leaking Routes
Redistribution
  Redistributing into ISIS
    Static -> ISIS
    OSPF -> ISIS
  Out of ISIS
Learning More
References


Copyright © 2001 Genium Publishing Corporation