NETGEAR S3300-28X (GS728TX) 24x1GE - Инструкция по эксплуатации - Страница 345

 Configuration Examples

345

 S3300 Smart Managed Pro Switch

•

Mark 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.

•

Mark 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.

•

Policy

. 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

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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, IP DSCP, or IP Precedence fields 
designating the incoming color value to be used as the conforming color. The color of 
exceeding traffic can 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. For 
more information, see 

Service Statistics 

on page 238.

•

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 can also be specified along 
with a QoS queue assignment.

DiffServ Configuration Example

To create a DiffServ Class/Policy and attach it to a switch interface, follow these steps:

1. 

From the QoS Class Configuration screen, create a new class with the following 
settings:

•

Class Name

. Class1