Update README.md ActiveMQ (#904)

* Update README.md

* Update README.md

k8s/activemq/README.md

@@ -12,7 +12,11 @@ Popular open stacks on Kubernetes, packaged by Google.
 
 ![Architecture diagram](resources/activemq-k8s-app-architecture.png)
 
-# TODO Architecture overview
+A Kubernetes Deployment manages ActiveMQ 5 single broker. 
+This deployment is based on default ActiveMQ 5 broker which has no authentication enabled for the subscribers.
+As a Database, it uses embedded KahaDB with persistent volume which is 5Gi by default in this deployment. 
+
+Access to the ActiveMQ service is authenticated and credentials are stored in Kubernetes Secret resource.
 
 # Installation
 
@@ -133,10 +137,9 @@ Set the storage class for the persistent volume of ActiveMQ's embedded KahaDB:
 > Note: "ssd" type storage is recommended for ActiveMQ, as it uses local disk to store and retrieve keys and values.
 > To create a StorageClass for dynamic provisioning of SSD persistent volumes, check out [this documentation](https://cloud.google.com/kubernetes-engine/docs/how-to/persistent-volumes/ssd-pd) for more detailed instructions.
 ```shell
-export ETCD_STORAGE_CLASS="ssd-storageclass" # If you don't set this value, default StorageClass will be used.
 export STORAGE_CLASS="standard" # provide your StorageClass name if not "standard"
 export PERSISTENT_DISK_SIZE="5Gi"
-```	```
+```
 
 #### Create namespace in your Kubernetes cluster