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