A platform engineer is comparing the pluggable interfaces Kubernetes relies on. One interface defines how Pod network connectivity is configured, including allocating each Pod an IP address and attaching it to the cluster network. Which interface provides this function?
- AContainer Runtime Interface (CRI), the standard that lets the kubelet manage containers through pluggable container runtimes.
- BContainer Storage Interface (CSI), the standard that lets external storage systems attach and mount persistent volumes into Pods.
- CService Mesh Interface (SMI), the specification that standardises traffic policy and telemetry across service mesh implementations.
- DContainer Network Interface (CNI), the standard that plugins implement to set up Pod network connectivity and IP allocation. Correct
Why A is wrong: Tempting because CRI is another container-layer interface the kubelet depends on, but it governs starting and stopping containers, not assigning Pod IP addresses.
Why B is wrong: Tempting because CSI is a similarly named pluggable interface, but it handles persistent storage provisioning and mounting rather than network connectivity.
Why C is wrong: Tempting because SMI relates to network traffic, but it defines higher-level mesh policy and does not assign Pod IPs or configure the base pod network.
Why D is correct: Correct because Kubernetes delegates pod networking to CNI plugins, which assign each Pod an IP and connect it to the cluster network according to the CNI specification.