NSM saves and archives the configuration changes both before and after they are implemented. This makes it easy for you to audit the changes that are being made by all the users to firewall address objects or groups. It is easy to trace or dive deeper into the changes that impact the overall security of the devices, especially when managing multiple firewalls in an environment.
For example, A device group has been added by someone in the network, during the past week. This change may not have any direct changes on the firewalls. But you can easily identify the changes in the NSM Audit, that a specific user has created a device group and has moved some firewalls under it.
The Audit option helps you to validate the backups for your restored firewall configuration. You can see the complete changes in JSON view by accessing Config Mgmt > Audit. You can also select two different items and execute a comparative analysis.