One of the type of proxy base license is an offline license where usually this is needed in a closed network where a direct connection to the internet by the appliance is not allowed.
Release : 6.7, 7.2 and 7.3
Component : Proxy base license.
Below are the steps to view whether the license on the proxy appliance is an offline license or not.
1. Download the license file from the Entitlement portal or support portal.
2. Open the license file and copy the content which is in a based 64 encoded.
3. Decode the content to ASCII. You can use one of the available online tool online to decode this.
On the decoded content, you will notice the following line that says "VA Offline Support".
<ProductDescription>Offline License for SWG V100</ProductDescription>
<ComponentName>VA Offline Support</ComponentName>