NETGEAR GS724TS-100NAS manual GS716Tv2 and GS724Tv3 Software Administration Manual

GS716Tv2 and GS724Tv3 Software Administration Manual

•Dropping: drop a packet upon arrival. This is useful for emulating access control list operation using DiffServ, especially when DiffServ and ACL cannot co-exist on the same interface.

•Marking IP DSCP or IP Precedence: marking/re-marking the DiffServ code point in a packet with the DSCP value representing the service level associated with a particular DiffServ traffic class. Alternatively, the IP Precedence value of the packet can be marked/re-marked.

•Marking CoS (802.1p): sets the three-bit priority field in the first/only 802.1p header to a specified value when packets are transmitted for the traffic class. An 802.1p header is inserted if it does not already exist. This is useful for assigning a layer 2 priority level based on a DiffServ forwarding class (i.e., DSCP or IP Precedence value) definition to convey some QoS characteristics to downstream switches which do not routinely look at the DSCP value in the IP header.

•Policing: a method of constraining incoming traffic associated with a particular class so that it conforms to the terms of the TCS. Special treatment can be applied to out-of-profile packets that are either in excess of the conformance specification or are non-conformant. The DiffServ feature supports the following types of traffic policing treatments (actions):

•drop: the packet is dropped

•mark cos: the 802.1p user priority bits are (re)marked and forwarded

•mark dscp: the packet DSCP is (re)marked and forwarded

•mark prec: the packet IP Precedence is (re)marked and forwarded

•send: the packet is forwarded without DiffServ modification

Color Mode Awareness: Policing in the DiffServ feature uses either color blind or color aware mode. Color blind mode ignores the coloration (marking) of the incoming packet. Color aware mode takes into consideration the current packet marking when determining the policing outcome. An auxiliary traffic class is used in conjunction with the policing definition to specify a value for one of the 802.1p, Secondary 802.1p, IP DSCP, or IP Precedence fields designating the incoming color value to be used as the conforming color. The color of exceeding traffic may be optionally specified as well.

•Counting: updating octet and packet statistics to keep track of data handling along traffic paths within DiffServ. In this DiffServ feature, counters are not explicitly configured by the user, but are designed into the system based on the DiffServ policy being created. See the Statistics section of this document for more details.

•Assigning QoS Queue: directs traffic stream to the specified QoS queue. This allows a traffic classifier to specify which one of the supported hardware queues are used for handling packets belonging to the class.

•Redirecting: forces classified traffic stream to a specified egress port (physical or LAG). This can occur in addition to any marking or policing action. It may also be specified along with a QoS queue assignment.

Appendix B: Configuration Examples 257