Netgear GS748Tv5 - ProSAFE 48-port Gigabit Smart Switch Guia Do Administrador

Layer 4 protocol (such as TCP or UDP)

Layer 4 source/destination ports

Source/destination IP address

From a DiffServ point of view, there are two types of classes:

DiffServ traffic classes

DiffServ service levels/forwarding classes

With DiffServ, you define which traffic classes to track on an ingress interface. You can define 
simple BA classifiers (DSCP) and a wide variety of multifield (MF) classifiers:

Layer 2; Layers 3, 4 (IP only)

Protocol-based

Address-based

You can combine these classifiers with logical AND or OR operations to build complex 
MF-classifiers (by specifying a class type of all or any, respectively). That is, within a single 
class, multiple match criteria are grouped together as an AND expression or a sequential OR 
expression, depending on the defined class type. Only classes of the same type can be 
nested; class nesting does not allow for the negation (i.e., exclude option) of the referenced 
class.

To configure DiffServ, you must define service levels, namely the forwarding classes/PHBs 
identified by a given DSCP value, on the egress interface. These service levels are defined 
by configuring BA classes for each.

Use DiffServ policies to associate a collection of classes that you configure with one or more 
QoS policy statements. The result of this association is referred to as a policy. 

From a DiffServ perspective, there are two types of policies:

Traffic Conditioning Policy. A policy applied to a DiffServ traffic class

Service Provisioning Policy. A policy applied to a DiffServ service level

You must manually configure the various statements and rules used in the traffic conditioning 
and service provisioning policies to achieve the desired Traffic Conditioning Specification 
(TCS) and the Service Level Specification (SLS) operation, respectively.