The command "filter access-group 10" is used to filter the ERSPAN session packets only to interface GigabitEthernet1. In the provided configuration snippet, an access list (numbered 10) is defined to permit traffic from IP address 10.10.10.1. This access list is then applied as a filter to the ERSPAN session using the "filter access-group 10" command, ensuring that only packets matching the criteria of the access list are captured in the ERSPAN session. References := Cisco's official documentation on configuring ERSPAN