The Cisco 10000 series Performance Routing Engine 4 (PRE4) addresses the demand for increased performance, scalability, and Hierarchical Quality of Service (HQoS) to support diverse network-edge requirements for residential and business services markets.Designed to meet requirements from service providers for high-capacity aggregation with sophisticated IP services, the Cisco 10000 series PRE4 uses the latest generation of the Cisco patented Parallel Express Forwarding (PXF) technology. PXF is a parallel multiprocessor architecture that enables deployment of multiple IP services while maintaining peak performance throughput. The PRE4 also supports the flexible Hierarchal Queuing Framework (HQF) available on the Cisco 10000 series routers. The HQF implementation on the PRE4 allows three levels (class, logical, and physical) of scheduling to apply queuing and shaping.