 when a router receives or sends a packet on its interface, it needs to inherently keep a count of that packet for various reasons. We recommend that such natively derived data con- tinue to be collected on the router. Another example would be error counts kept by the router related to internal packet handling. However, any synthetic measurement functions that may have been previ- ously integrated into the network element should be decoupled and implemented separately. The overall measurement framework consists of the following: 1. Component-level measurements, focusing on measuring the health of individual network components 2. Service and network measurements between edges of the network, and includes the use of active, passive, and hybrid techniques 3. Measurement instrumentation orchestration 4. Telemetry, focused on efficient transport of measurement data between remote and central collectors The measurement framework outlined herein is extensible to include other measurement dis- ciplines within the common framework. We continuously evaluate the need to include such new mechanisms, as and when the need arises. The next few sections cover the details of each of these areas. 16.4.3 COMPONENT-LEVEL MEASUREMENTS Component-level measurements cover network-element-specific measurements and are described in detail in Chapter 3. This functionality typically includes monitoring the utilization of CPU, mem- ory, storage, links, and queues, monitoring of component-level errors, etc. Building the Network of the Future QoS YANG POLLED STATE STREAMING ROUTING PROTOCOL (NETCONF/RESTCONF/ TELEMETRY YANG) (APACHEAVRO/YANG) INTERFACE YANG DEVICE YANG YANG MODELS (Configuration and State) NETWORK ELEMENT (COMPONENT) FIGURE 16.8 Component measurement instrumentation framework. The overall approach is to implement component measurements for network elements via a YANG model-based approach, as shown in Figure 16.8. Utilizing YANG models that cover not only the configuration but also the operational state of various feature compo