Core Concepts and Design

Plug and play switches

  • Chance for failure

  • Broadcast traffic

  • Multicast issues

  • Security issues

  • MAC flooding

Enterprise Composite Network Model

  • Access

  • Distribution

  • Core

VLANs

  • Simpler Management

  • Troubleshooting ease

  • Better performance

  • Mental sanity

  • Summarization points

Designing the Network

  • Restrict VLANs to switch blocks

  • Implement management VLAN

  • Separate voice traffic

  • Implement multicast support

The Two Flavours of CISCO Switches

  • CISCO catalyst OS (CatOS)

    • Uses set-based syntax

    • Typically combined with IOS for layer 3 functions

  • CISCO ‘native’ IOS

    • Similar to router configuration

  • Typically, all larger switch models (such as cat 4500, 6500, etc…) run CatOS

  • CISCO has a migration path for all mainline switches to the native IOS