updating readme

Author: kirankotari

README.md

@@ -41,6 +41,66 @@ ncs-netsim, It's a powerful tool to build a simulated network environment for Ne
 
 netsim-wrapper, An open space to automate the ncs-netsim.
 
+You can build your netsim network using JSON/YAML templates as follows
+
+**creating device using YAML file**
+```
+nso-packages-path: ./nso-run/package
+download-neds: false
+neds:
+- https://earth.tail-f.com:8443/ncs-pkgs/cisco-ios/5.7.1/ncs-5.7.1-cisco-ios-6.79.signed.bin
+compile-neds: false
+packages-reload: false
+start-devices: true
+add-to-nso: true
+add-authgroup-to-nso: false
+authgroup:
+  type: local
+  path: ./custom_authgroup.xml
+device-mode:
+  name-based:
+    cisco-ios-cli-6.79:
+    - device-ios0
+    - device-ios1
+load-day0-config: false
+config-path: ../day0/
+config-files:
+- device_ios0_interface.cfg
+- device_ios1_interface.cfg
+```
+
+**creating network using JSON format**
+```
+{
+  "nso-packages-path": "./nso-run/packages",
+  "download-neds": true,
+  "neds": [
+    "https://earth.tail-f.com:8443/ncs-pkgs/cisco-ios/5.7.1/ncs-5.7.1-cisco-ios-6.79.signed.bin"
+  ],
+  "compile-neds": true,
+  "packages-reload": true,
+  "start-devices": true,
+  "add-to-nso": true,
+  "add-authgroup-to-nso": true,
+  "authgroup": {
+    "type": "system"
+  },
+  "device-mode": {
+    "prefix-based": {
+      "cisco-ios-cli-6.79": {
+        "count": 2,
+        "prefix": "network-ios"
+      }
+    }
+  },
+  "load-day0-config": true,
+  "config-path": "./day0/",
+  "config-files": [
+    "network_ios0_interface.cfg",
+    "network_ios1_interface.cfg"
+  ]
+}
+```
 ## Pre-requisites
 
 - ncs-netsim command must be reconginsed by the terminal.