doc(policy): update README

Signed-off-by: Georgios Katsikas <katsikas.gp@gmail.com>

src/policy/README.md

-# Policy Management TeraFlow OS service
+# TeraFlowSDN Policy Management service
 
-The Policy Management service is tested on Ubuntu 20.04. Follow the instructions below to build, test, and run this service on your local environment.
+This repository hosts the TeraFlowSDN Policy Management service.
+Follow the instructions below to build, test, and run this service on your local environment.
 
-## Compile code
+## TeraFlowSDN Policy Management service architecture
 
-`
+The TeraFlowSDN Policy Management service architecture consists of ten (10) interfaces listed below:
+
+Interfaces |
+|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+|  1. The `PolicyGateway` interface that implements all the RPC functions that are described in `policy.proto` file. |
+|  2. The `MonitoringGateway` interface that communicates with a `Monitoring` service gRPC client to invoke key RPC functions described in `monitoring.proto` file. |
+|  3. The `ContextGateway` interface that communicates with a `Context` service gRPC client to invoke key RPC functions described in `context.proto` file. |
+|  4. The `ServiceGateway` interface that communicates with a `Service` service gRPC client to invoke key RPC functions described in `service.proto` file. |
+|  5. The `DeviceGateway` interface that communicates with a `Device` service gRPC client to invoke key RPC functions described in `device.proto` file. |
+|  6. The `PolicyService` interface that implements the Policy RPC methods by communicating with a `Monitoring` gRPC client, a `Context` gRPC client, a `Service` gRPC client, and a `Device` gRPC client through the `MonitoringService`, `ContextService`, `ServiceService`, and `DeviceService` interfaces respectively. |
+|  7. The `MonitoringService` interface that implements the `SetKpiAlarm()` and `GetAlarmResponseStream()` methods by communicating with a `Monitoring` gRPC client through the use of the `MonitoringGateway` interface. |
+|  8. The `ContextService` interface that implements the `GetService()`, `GetDevice()`, `GetPolicyRule`, `SetPolicyRule`, and `DeletePolicyRule` methods by communicating with a `Context` gRPC client through the use of the `ContextGateway` interface. |
+|  9. The `ServiceService` interface that implements the `UpdateService()` method by communicating with a `Service` gRPC client through the use of the `ServiceGateway` interface. |
+| 10. The `DeviceService` interface that implements the `ConfigureDevice()` method by communicating with a `Device` gRPC client through the use of the `DeviceGateway` interface. |
+
+## Prerequisites
+
+The TeraFlowSDN Policy Management service is currently tested against Ubuntu 20.04 and Java 11.
+
+To quickly install Java 11 on a Debian-based Linux distro do:
+
+```bash
+sudo apt-get install openjdk-11-jdk -y
+```
+
+Feel free to try more recent Java versions.
+
+## Compile
+
+```bash
 ./mvnw compile
-`
-## Execute unit tests
+```
 
-`
+## Run tests
+
+```bash
 ./mvnw test
-`
+```
+
 ## Run service
 
-`
+```bash
 ./mvnw quarkus:dev
-`
+````
+
+## Clean
+
+```bash
+./mvnw clean
+```
+
+## Deploying on a Kubernetes cluster
+
+To create the K8s manifest file under `target/kubernetes/kubernetes.yml` to be used run
+
+```bash
+./mvnw clean package -DskipUTs -DskipITs
+```
+
+To deploy the application in a K8s cluster run
+
+```bash
+kubectl apply -f "manifests/policyservice.yaml"
+```
+
+## Maintainers
+
+This TeraFlowSDN service is implemented by [UBITECH](www.ubitech.eu).
+
+Feel free to contact Georgios Katsikas (gkatsikas at ubitech dot eu) in case you have questions.