An ACL affords a system administrator the ability to grant or restrict client access by specifying that traffic from a specific host or a specific network to either be denied or permitted.
IP based firewalls function like Access Control Lists (ACLs) to filter/mark packets, as opposed to filtering packets on layer 2 ports. IP firewalls implement uniquely defined access control policies, so if you do not have an idea of what kind of access to allow or deny, a firewall is of little value, and could provide a false sense of network security.
IP based firewall rules are specific to source and destination IP addresses and the unique rules and precedence orders assigned. Both IP and non-IP traffic on the same Layer 2 interface can be filtered by applying an IP ACL. Firewall rules are processed by a firewall supported device from first to last. When a rule matches the network traffic a controller or service platform is processing, the firewall uses that rule's action to determine whether traffic is allowed or denied.
To configure an extended ACL on EX3500:
EX3500 extended ACL configurations can either be modified as a collective group of variables or selected and updated individually if their filtering attributes require a more refined update.
