e 12.5) of input/output (IO) management, packet pipeline, data plane management, control plane management, and vPE OSS. The IO manager processes pack- ets from the server network interface controller (NIC) card into the packet pipeline and includes MPLS/VLAN label management functions. One or more packet pipelines perform the match action processing of packets as well as scheduling functions such as class of services. The data plane man- ager determines how to direct packet flows to which pipeline. The control plane manager serves as a local autonomous control plane and responds in real time to BGP, bidirectional forwarding detection (BFD), etc. messages. And the OSS manages configuration of the vPE software as well as communicates telemetry upstream to ONAP (see Chapter 7). For low throughput vPE applications (<1 Gbps), the five functional modules may run on a single CPU. For high throughput vPE applications (>10 Gbps), a common strategy is to split the functional modules across multiple server CPUs or even split across multiple servers to maximize performance using parallel processing. Interestingly, the first routers were in fact software running on general purpose CPUs. As routing started to take off, the ability of software and CPUs to handle increasing packet throughputs hit fundamental limits of CPU and software technology. The industry turned to custom application-specific integrated circuits to address the throughput requirements because of bandwidth growth and several companies emerged to create products that combined custom silicon and software into integrated vertical router solutions. This model dominated the networking indus- try for two decades. In a "Back to the Future" moment, what happened in the intervening years was Moore's law and high levels of integration of multiple CPU on a single chip resulted in increased performance to the point that software routers were able to displace vertically integrated router for multiple throughput speed tiers. In particular, the speed tiers of interest are ti