* This includes UDP, non-compliant HTTP, server-first protocols, stateful sets, external services, etc.
  * Explicitly opting into behavioral changes can be acceptable. For example, introducing Istio multi-cluster semantics.
* Ensure traffic between mesh workloads is securely encrypted with an Istio identity.
* Be lightweight enough to not limit adoption.

```console
helm show values istio/ztunnel
```

### Profiles

Istio Helm charts have a concept of a `profile`, which is a bundled collection of value presets.
These can be set with `--set profile=<profile>`.
For example, the `demo` profile offers a preset configuration to try out Istio in a test environment, with additional features enabled and lowered resource requirements.

	"istio.io/istio/pkg/kube/labels"
	"istio.io/istio/pkg/log"
	"istio.io/istio/pkg/slices"
	"istio.io/istio/pkg/url"
)

var (
	errMissingFilename = errors.New(`error: you must specify resources by --filename.
Example resource specifications include:
   '-f rsrc.yaml'
   '--filename=rsrc.json'`)

	validFields = map[string]struct{}{
		"apiVersion": {},
		"kind":       {},
		"metadata":   {},
		"spec":       {},

  // that is used when creating the resources.
  // +optional
  optional string apiGroup = 1;

  // Resource is the type of resource being referenced, for example "pods".
  optional string resource = 3;

  // Name is the name of resource being referenced.
  optional string name = 4;

  // UID identifies exactly one incarnation of the resource.
  optional string uid = 5;

  // are specific to the node & CRI configuration.  It is assumed that all
  // handlers are available on every node, and handlers of the same name are
  // equivalent on every node.
  // For example, a handler called "runc" might specify that the runc OCI
  // runtime (using native Linux containers) will be used to run the containers
  // in a pod.

```

## Other Reference

The framework for this implementation of the CNI plugin is based on the
[containernetworking sample plugin](https://github.com/containernetworking/plugins/tree/main/plugins/sample)

The details for the deployment & installation of this plugin were pretty much lifted directly from the
[Calico CNI plugin](https://github.com/projectcalico/cni-plugin).

Specifically:

message PodDisruptionBudgetSpec {
  // An eviction is allowed if at least "minAvailable" pods selected by
  // "selector" will still be available after the eviction, i.e. even in the
  // absence of the evicted pod.  So for example you can prevent all voluntary
  // evictions by specifying "100%".
  // +optional
  optional k8s.io.apimachinery.pkg.util.intstr.IntOrString minAvailable = 1;

  // number of DaemonSet pods at the start of the update (ex: 10%). Absolute
  // number is calculated from percentage by rounding up.
  // This cannot be 0 if MaxSurge is 0
  // Default value is 1.
  // Example: when this is set to 30%, at most 30% of the total number of nodes
  // that should be running the daemon pod (i.e. status.desiredNumberScheduled)
  // can have their pods stopped for an update at any given time. The update

  // will be forwarded to.
  optional IngressBackend backend = 2;
}

// HTTPIngressRuleValue is a list of http selectors pointing to backends.
// In the example: http://<host>/<path>?<searchpart> -> backend where
// where parts of the url correspond to RFC 3986, this resource will be used
// to match against everything after the last '/' and before the first '?'
// or '#'.

```console
helm show values istio/istiod
```

### Profiles

Istio Helm charts have a concept of a `profile`, which is a bundled collection of value presets.
These can be set with `--set profile=<profile>`.
For example, the `demo` profile offers a preset configuration to try out Istio in a test environment, with additional features enabled and lowered resource requirements.