Every so often someone tries to apply the “let all be friends and love each other” mentality to LAN networks and designs a pure layer-2 switched LAN (because it’s simpler). Jay contributed a ten-step “what happens next” description in his comment to my “Lies, damned lies and product marketing” post. The steps are so hilarious I simply had to repost them:

1. Build everything at layer 2 because "it's simpler".
2. Scale a little.
3. Things start breaking mysteriously. Run around in circles. Learn about packet sniffers and STP.
4. Learn about layer 3 features in switches you already own. Start routing.
5. Scale more.
6. Things start breaking mysteriously. Learn about TCAMs. Start wishing for NetFlow.
7. Redesign. Buy stuff.
8. Scale more.
9. VMWare jockeys start asking about bridging across the WAN.
10. Enroll in hair loss program.