**Istio vs K8S: Understanding the Complexity**

As an experienced developer, I understand that Istio and Kubernetes (K8S) serve different purposes and have distinct levels of complexity. In this article, I will guide you through the process of implementing Istio compared to Kubernetes, and explain why Istio is considered more complex.

**Step-by-Step Process Overview**

| **Step** | **Description** | **Code Example** |
|----------|------------------------------------------------------|----------------------------------------------------------|
| Step 1 | Install Kubernetes | `brew install kubectl` |
| Step 2 | Set up Kubernetes cluster | `kubectl create -f cluster.yaml` |
| Step 3 | Install Istio toolkit | `curl -L https://istio.io/downloadIstio | ISTIO_VERSION=1.11.3` |
| Step 4 | Deploy Istio on Kubernetes cluster | `istioctl install --set profile=demo` |
| Step 5 | Enable Istio sidecar injection for Kubernetes pods | `kubectl label namespace default istio-injection=enabled`|
| Step 6 | Deploy sample application with Istio | `kubectl apply -f samples/bookinfo/platform/kube/bookinfo.yaml` |
| Step 7 | Set up Istio gateway and virtual services | `kubectl apply -f samples/bookinfo/networking/bookinfo-gateway.yaml` |
| Step 8 | Access the sample application through Istio gateway | Open browser and go to `https://$GATEWAY_URL/productpage` |

**Step-by-Step Implementation**

**Step 1: Install Kubernetes**
```
brew install kubectl
```
- This command installs the Kubernetes command-line tool on your local machine.

**Step 2: Set up Kubernetes cluster**
```
kubectl create -f cluster.yaml
```
- Use a YAML configuration file to create a Kubernetes cluster with the desired specifications.

**Step 3: Install Istio toolkit**
```
curl -L https://istio.io/downloadIstio | ISTIO_VERSION=1.11.3
```
- Download the Istio toolkit installer with the specified version.

**Step 4: Deploy Istio on Kubernetes cluster**
```
istioctl install --set profile=demo
```
- Use Istio control plane to install Istio on the Kubernetes cluster with a specified configuration profile (e.g., demo).

**Step 5: Enable Istio sidecar injection for Kubernetes pods**
```
kubectl label namespace default istio-injection=enabled
```
- Label the default namespace to enable automatic Istio sidecar injection for all new pods deployed in the namespace.

**Step 6: Deploy sample application with Istio**
```
kubectl apply -f samples/bookinfo/platform/kube/bookinfo.yaml
```
- Deploy a sample application called Bookinfo on the Kubernetes cluster with Istio sidecars injected into the pods.

**Step 7: Set up Istio gateway and virtual services**
```
kubectl apply -f samples/bookinfo/networking/bookinfo-gateway.yaml
```
- Define Istio gateway and virtual services to route traffic to different versions of the Bookinfo application.

**Step 8: Access the sample application through Istio gateway**
- Open a web browser and go to `https://$GATEWAY_URL/productpage` to access the Bookinfo application through the Istio gateway. Replace `$GATEWAY_URL` with the actual URL.

In conclusion, Istio introduces additional complexity compared to Kubernetes by adding a service mesh layer for traffic management, security, and observability. By following the step-by-step process outlined above, you can gain a better understanding of why Istio is considered more complex than Kubernetes. Good luck with your Istio journey!