Section 12.5: Core Layer Policy
The core block is responsible for moving data quickly. All the devices that are designed to be core block solutions are optimized to move data as quickly as possible. For this reason, the core block should have as little policy as possible. The only policies that should be applied at the core block are those that relate to quality of service (QoS) commands for congestion management and congestion avoidance. QoS implementations vary, depending on hardware used and versions of IOS. Please see your IOS-specific documentation for details.