Caching is individually enabled on video server for subscribers by SM fdpi_ctrl utility.
Example: activate caching for all subscribers:
fdpi_ctrl load --service 7 --cidr 192.168.1.0/24 --cidr 192.168.2.0/24
Here 192.168.1.0/24 and 192.168.2.0/24 are ASN addresses ranges of the operator