Chapter 100 Firewall Filters—Overview - Dell PowerConnect J-EX4200-24T Software Manual

CHAPTER 100
Firewall Filters—Overview
Firewall Filters for J-EX Series Switches Overview
Firewall Filter Types
Firewall Filters for J-EX Series Switches Overview on page 2721
Understanding Planning of Firewall Filters on page 2724
Understanding Firewall Filter Processing Points for Bridged and Routed Packets on
J-EX Series Switches on page 2726
Understanding How Firewall Filters Control Packet Flows on page 2727
Firewall Filter Match Conditions and Actions for J-EX Series Switches on page 2728
Understanding How Firewall Filters Are Evaluated on page 2746
Understanding Firewall Filter Match Conditions on page 2748
Understanding How Firewall Filters Test a Packet's Protocol on page 2752
Understanding the Use of Policers in Firewall Filters on page 2752
Understanding Filter-Based Forwarding for J-EX Series Switches on page 2753
Firewall filters provide rules that define whether to permit, deny, or forward packets that
are transiting an interface on a J-EX Series Switch from a source address to a destination
address. You configure firewall filters to determine whether to permit, deny, or forward
traffic before it enters or exits a port, VLAN, or Layer 3 (routed) interface to which the
firewall filter is applied. An ingress firewall filter is a filter that is applied to packets that
are entering a network. An egress firewall filter is a filter that is applied to packets that
are exiting a network. You can configure firewall filters to subject packets to filtering,
class-of-service (CoS) marking (grouping similar types of traffic together, and treating
each type of traffic as a class with its own level of service priority), and traffic policing
(controlling the maximum rate of traffic sent or received on an interface).
Firewall Filter Types on page 2721
Firewall Filter Components on page 2722
Firewall Filter Processing on page 2723
The following firewall filter types are supported for J-EX Series switches:
Port (Layer 2) firewall filter—Port firewall filters apply to Layer 2 switch ports. You can
apply port firewall filters in both ingress and egress directions on a physical port.
2721