Updated phase6.md

docs/phases/phase6.md

@@ -1,3 +1,56 @@
 ## 🔍 Phase 6 - Non-Functional Requirements and Technical Architecture or Big Data
 
-TODO
+## 1. Planned Improvements
+
+### 1.1 Architecture Update
+We plan to update the architecture diagram to provide a more accurate representation of:
+
+* The internal communication between microservices via gRPC.
+* The gRPC Gateway responsible for converting REST requests to gRPC.
+* The ingress flow, now using GKE’s native Ingress controller instead of Traefik.
+
+### 1.2 Migration to GKE Ingress
+To simplify deployment and maintenance, we will remove the Traefik Ingress Controller and adopt the native GKE Ingress. This improves integration with GCP’s load balancing.
+
+### 1.3 Authentication with Keycloak
+We will introduce authentication and authorization by integrating [Keycloak](https://www.keycloak.org/) as the Identity Provider. Keycloak will manage user sessions, tokens (OIDC), and role-based access control (RBAC) across the services.
+
+### 1.4 CI/CD Pipeline
+A continuous integration and deployment (CI/CD) pipeline will be implemented using GitHub Actions and GKE. It will:
+
+* Update OpenAPI specification files.
+* Build images.
+* Deploy services to the cluster.
+
+### 1.5 Liveness and Readiness Probes
+To improve fault tolerance and enable better self-healing behavior in Kubernetes, we will define:
+
+* **Liveness probes** to detect and restart failed containers.
+* **Readiness probes** to ensure that traffic is only sent to containers that are ready to handle requests.
+
+### 1.6 Resource Limits and HPA
+We will benchmark services to determine ideal values for:
+
+* **CPU and memory resource requests/limits**.
+* **Horizontal Pod Autoscaling (HPA)** thresholds to ensure scalability based on real traffic patterns.
+
+## 2. Non-Functional Requirements
+| Category        | Requirement                                                                |
+| --------------- | -------------------------------------------------------------------------- |
+| Scalability     | Use HPA to autoscale services based on CPU usage.                          |
+| Availability    | Configure liveness/readiness probes and multiple replicas where necessary. |
+| Security        | Enforce authentication and authorization via Keycloak.                     |
+| Maintainability | Implement CI/CD for consistent, automated deployments.                     |
+
+## 3. Deployment Plan
+| Step                            | Tool/Technology       |
+| ------------------------------- | --------------------- |
+| Containerization                | Docker                |
+| Cluster Orchestration           | Kubernetes (GKE)      |
+| Ingress Management              | GKE Native Ingress    |
+| Identity and Access Management  | Keycloak (OIDC, RBAC) |
+| CI/CD                           | GitHub Actions + GKE  |
+| Autoscaling                     | Kubernetes HPA        |
+
+## 4. Architecture Diagram
+![application architecture](../images/architecture.png)