GS752TP, GS728TP, and GS728TPP Gigabit Smart Switches

Dropping. Drops 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. Marks and remarks the DiffServ code point in a packet with the DSCP value representing the service level associated with a particular DiffServ traffic class.

Marking CoS (802.1p). Sets the 3-bit priority field in the first or 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 exist. This is useful for assigning a Layer 2 priority level based on a DiffServ forwarding class (that is, DSCP or IP precedence value) definition to convey some QoS characteristics to downstream switches that do not routinely look at the DSCP value in the IP header.

Policing. A method of limiting 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. 802.1p user priority bits are marked or re-marked and forwarded.

Mark DSCP. The packet DSCP is marked or 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 considers the current packet marking when determining the policing outcome. An auxiliary traffic class is used with the policing definition to specify a value for one of the 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 might be optionally specified as well.

Counting. Updates 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. For more information, see Switch Statistics on page 208.

Assigning QoS Queue. Directs traffic stream to the specified QoS queue. This enables a traffic classifier to specify which one of the supported hardware queues is used for handling packets belonging to the class.

Sample DiffServ Configuration

To create a DiffServ Class or Policy and attach it to a switch interface:

1.In the QoS Class Configuration screen, create a class with the following settings:

Class Name. Class1

Class Type. All

For more information about this screen, see Class Configuration on page 147.

2.Click Class1 to view the DiffServ Class Configuration screen for this class.

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NETGEAR GS752TP, GS728TPP manual Sample DiffServ Configuration, Class Name. Class1 Class Type. All