Introduction, Motivation and Historical Background -- Router Architecture -- to the IOS and JUNOS Command Line Interface -- IS-IS Basics -- Neighbour Discovery and Handshaking -- Generating, Flooding and Ageing LSPs -- Pseudonodes and Designated Routers -- Synchronizing Databases -- Fragmentation -- SPF and Route Calculation -- TLVs and Sub-TLVs -- IP Reachability Information -- IS-IS Extension…