646 QoS CommandsA user configures an ACL permit rule to force its matching traffic stream to aspecific egress interface, bypassing any forwarding decision normallyperformed by the device. The interface can be a physical port or a LAG. Theredirect interface rule action is independent of, but compatible with, theassign queue rule action.ACLs can be configured to apply to a VLAN instead of an interface. Traffictagged with a VLAN ID (either receive-tagged or tagged by ingress processsuch as PVID) is evaluated for a match regardless of the interface on which itis received.Layer 2 ACLsThe Layer 2 ACL feature provides access list capability by allowingclassification on the Layer 2 header of an Ethernet frame, including the802.1Q VLAN tag(s). In addition, the rule action set is enhanced to designatewhich (egress) CoS queue should handle the traffic, and whether the trafficflow is to be redirected to a specific outgoing interface.MAC access lists are identified by a user-specified name instead of a number.Layer 3/4 IPv4 ACLsThe Layer 3/4 ACL feature supports IP access lists, both standard andextended. These lists check the Layer 3 portion of a packet, lookingspecifically at information contained in the IP header and, in certain cases,the TCP or UDP header. An Ethertype of 0x0800 is assumed in the case of IPaccess lists. Permit and deny actions are supported for each ACL rule.Standard layer 3/4 ACLs can be classified based on the source IP address andnetmask or other extended classification criteria.Class of Service (CoS)The PowerConnect CoS Queueing feature allows the user to directlyconfigure device queueing and, therefore, provide the desired QoS behaviorwithout the complexities of DiffServ. The CoS feature allows the user todetermine the following queue behavior:• Queue Mapping– Trusted Port Queue Mapping