diff --git a/configuration/config.rst b/configuration/config.rst
index fe0c678..b83b16e 100644
--- a/configuration/config.rst
+++ b/configuration/config.rst
@@ -22,115 +22,224 @@
         - REST APIs are defined to create/modify/delete network slice.
         - REST APIs are also provided to provision subscribers and grouping the subscribers under device Group.
 
-Configuration
--------------
+Configuration Steps
+-------------------
 This Configuration describes what to configure at high level from RoC/SIMAPP. ConfigPod stores this configuration
-and publish to respective clients over grpc.
+and publish to respective clients over REST/grpc.
 
-    - Network Slice Configuration
+    - Step1 : Provision subscriber in 4G/5G subsystem
 
-        - Configuration to create a slice of network
-        - Slice contains the QoS configuration
-        - Group of devices assigned to network slice
+        - This step is used to configure IMSI in the SD-Core
+        - This procedure is used to configure security keys for a subscriber
+        - Subscribers can be created during system startup or later
+
+    - Step2 : Device Group Configuration
+
+        - Group multiple devices under device group
+        - Configure QoS for the device group
+        - Configure IP domain configuration for the device group e.g. MTU, IP Pool, DNS server
+
+
+    - Step3: Network Slice Configuration
+
+        - Configuration to create a Network Slice
+        - Add device Group into Network Slice
+        - Slice contains the Slice level QoS configuration
         - Site configuration including UPF, eNBs/gNBs assigned to the slice
+        - Applications allowed to be accessed by this slice
 
-    - Device Group Configuration
+Option I - Configuration using Simapp POD
+-----------------------------------------
 
-        - Configuration of group of Devices/Subscribers
-        - QoS required for the device group
-        - IP domain configuration for the device group
+Easiest way to configure SD-Core is to use simapp. Simapp is the POD which takes
+yaml configuration and configures the subscribers, device groups, network slices
 
-    - Device/Subscriber Provisioning
+.. code-block::
 
-        - Security keys for a subscriber or group of subscribers
+  config:
+    simapp:
+      cfgFiles:
+        simapp.yaml:
+          configuration:
+            provision-network-slice: true
+            sub-provision-endpt:
+              addr: config4g
+              port: 5000
+            subscribers:
+            - ueId-start: 208014567891201
+              ueId-end: 208014567891211
+              plmnId: 20801
+              opc: "d4416644f6154936193433dd20a0ace0"
+              op: ""
+              key: "465b5ce8b199b49faa5f0a2ee238a6bc"
+              sequenceNumber: 96
+            device-groups:
+            - name:  "4g-oaisim-user"
+              imsis:
+                - "208014567891201"
+                - "208014567891202"
+              ip-domain-name: "pool1"
+              ip-domain-expanded:
+                dnn: internet
+                dns-primary: "8.8.8.8"
+                mtu: 1460
+                ue-ip-pool: "172.250.0.0/16"
+                ue-dnn-qos:
+                  dnn-mbr-downlink: 20000000
+                  dnn-mbr-uplink: 4000000
+                  bitrate-unit: bps
+                  traffic-class:  #default bearer QCI/ARP
+                    name: "platinum"
+                    qci: 9
+                    arp: 1
+                    pdb: 300
+                    pelr: 6
+              site-info: "aiab"
+            network-slices:
+            - name: "default"
+              slice-id:
+                sd: "010203"
+                sst: 1
+              site-device-group:
+              - "4g-oaisim-user"
+              site-info:
+                gNodeBs:
+                - name: "aiab-gnb1"
+                  tac: 1
+                plmn:
+                  mcc: "208"
+                  mnc: "01"
+                site-name: "aiab"
+                upf:
+                  upf-name: "upf"
+                  upf-port: 8805
 
-Sample Configuration
---------------------
-Sample Network Slice Configuration through REST Interface
+Option II - Configuration using REST Interface
+----------------------------------------------
+
+You can decide to use any other tool to generate REST messages towards SD-Core to configure
+subscribers, device groups and network slice
+
+
+Subscriber Configuration through REST Interface
+"""""""""""""""""""""""""""""""""""""""""""""""
+
+Below example configures subscriber `208014567891209` in the SD-Core
+
+.. code-block::
+
+  - Post:
+    URL: `http://<config-service-name-or-ip>:<port>/api/subscriber/<imsi-xxx>`
+    Ex: `http://<config-service-name-or-ip>:<port>/api/subscriber/<imsi-208014567891209>`
+
+    Request Body:
+
+        {
+            "UeId":"208014567891209",
+            "plmnId":"20801",
+            "opc":"d4416644f6154936193433dd20a0ace0",
+            "key":"465b5ce8b199b49faa5f0a2ee238a6bc",
+            "sequenceNumber":"96"
+        }
+
+  - Delete:
+    URL: `http://<config-service-name-or-ip>:<port>/api/subscriber/<imsi-xxx>`
+    Ex: `http://<config-service-name-or-ip>:<port>/api/subscriber/<imsi-208014567891209>`
+
+
+Device Group Configuration through REST Interface
+"""""""""""""""""""""""""""""""""""""""""""""""""
+
+.. code-block::
+
+  - Post:
+    URL: `http://<config-service-name-or-ip>:<port>/device-group/<group-name>`
+    Ex: `http://config5g:8080/device-group/iot-camera`
+
+    Request Body:
+    {
+        "imsis":
+        [
+            "123456789123456"
+            "123456789123457"
+            "123456789123458"
+        ],
+        "site-info": "menlo",
+        "ip-domain-name": "pool1",
+        "ip-domain-expanded":
+        {
+            "dnn": "internet",
+            "ue-ip-pool": "10.91.0.0/16",
+            "dns-primary": "8.8.8.8",
+            "dns-secondary": "8.8.4.4",
+            "mtu": 1460,
+            "ue-dnn-qos":
+            {
+                "dnn-mbr-uplink": 4000000,
+                "dnn-mbr-downlink": 20000000,
+                "bitrate-unit": "Mbps",
+                "traffic-class": "platinum"
+            }
+        }
+    }
+
+  - Delete
+    URL: `http://<config-service-name-or-ip>:<port>/device-group/<group-name>`
+    Ex: `http://config5g:8080/device-group/iot-camera`
+
+Network Slice Configuration through REST Interface
+""""""""""""""""""""""""""""""""""""""""""""""""""
+
+.. code-block::
+
   - Post:
     URL: `http://<config-service-name-or-ip>:<port>/network-slice/<slice-name>`
     Ex: `http://config5g:8080/network-slice/slice1`
+
+
     Request Body:
     {
-    "slice-id": {
-    "sst": "1",
-    "sd": "010203"
-    },
-    "qos": {
-    "uplink": 4000000,
-    "downlink": 20000000,
-    "bitrate-unit": "Mbps",
-    "traffic-class": "platinum"
-    },
-    "site-device-group": [
-    "iot-camera"
-    ],
-    "site-info": {
-    "site-name": "menlo",
-    "plmn": {
-    "mcc": "315",
-    "mnc": "010"
-    },
-    "gNodeBs": [
-    {
-    "name": "menlo-gnb1",
-    "tac": 1
-    }
-    ],
-    "upf": {
-    "upf-name": "upf.menlo.aetherproject.org",
-    "upf-port": 8805
-    }
-    },
-    "deny-applications": [
-    "iot-app2"
-    ],
-    "permit-applications": [
-    "iot-app"
-    ],
-    "applications-information": [
-    {
-    "app-name": "iot-app",
-    "endpoint": "1.1.1.1/32",
-    "start-port": 40000,
-    "end-port": 40000,
-    "protocol": 17
-    }
-    ]
+        "slice-id":
+        {
+            "sst": "1",
+            "sd": "010203"
+        },
+        "qos":
+        {
+            "uplink": 4000000,
+            "downlink": 20000000,
+            "bitrate-unit": "Mbps",
+            "traffic-class": "platinum"
+        },
+        "site-device-group":
+        [
+            "iot-camera"
+        ],
+        "site-info":
+        {
+            "site-name": "menlo",
+            "plmn":
+            {
+                "mcc": "315",
+                "mnc": "010"
+            },
+            "gNodeBs":
+            [
+                {
+                "name": "menlo-gnb1",
+                "tac": 1
+                }
+            ],
+            "upf":
+            {
+            "upf-name": "upf.menlo.aetherproject.org",
+            "upf-port": 8805
+            }
+        },
     }
 
   - Delete
     URL: `http://<config-service-name-or-ip>:<port>/network-slice/<slice-name>`
     Ex: `http://config5g:8080/network-slice/slice1`
 
-Sample Device Group Configuration through REST Interface
-  - Post:
-    URL: `http://<config-service-name-or-ip>:<port>/device-group/<group-name>`
-    Ex: `http://config5g:8080/device-group/iot-camera`
-    Request Body:
-    {
-    "imsis": [
-    "123456789123456"
-    "123456789123457"
-    "123456789123458"
-    ],
-    "site-info": "menlo",
-    "ip-domain-name": "pool1",
-    "ip-domain-expanded": {
-    "dnn": "internet",
-    "ue-ip-pool": "10.91.0.0/16",
-    "dns-primary": "8.8.8.8",
-    "dns-secondary": "8.8.4.4",
-    "mtu": 1460,
-    "ue-dnn-qos": {
-    "dnn-mbr-uplink": 4000000,
-    "dnn-mbr-downlink": 20000000,
-    "bitrate-unit": "Mbps",
-    "traffic-class": "platinum"
-    }
-    }
-    }
 
-  - Delete
-    URL: `http://<config-service-name-or-ip>:<port>/device-group/<group-name>`
-    Ex: `http://config5g:8080/device-group/iot-camera`