SMC Networks 6128L2, Management Manual

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C
ONFIGURING THE
S
WITCH
3-196
All switches or routers that access the Internet rely on class information to
provide the same forwarding treatment to packets in the same class. Class
information can be assigned by end hosts, or switches or routers along the
path. Priority can then be assigned based on a general policy, or a detailed
examination of the packet. However, note that detailed examination of
packets should take place close to the network edge so that core switches
and routers are not overloaded.
Switches and routers along the path can use class information to prioritize
the resources allocated to different traffic classes. The manner in which an
individual device handles traffic in the DiffServ architecture is called
per-hop behavior. All devices along a path should be configured in a
consistent manner to construct a consistent end-to-end QoS solution.
Notes: 1. You can configure up to 16 rules per Class Map. You can also
include multiple classes in a Policy Map.
2. You should create a Class Map before creating a Policy Map.
Otherwise, you will not be able to select a Class Map from the
Policy Rule Settings screen.
Configuring Quality of Service Parameters
To create a service policy for a specific category or ingress traffic, follow
these steps:
1. Use the “Class Map” to designate a class name for a specific category
of traffic.
2. Edit the rules for each class to specify a type of traffic based on an
access list, a DSCP or IP Precedence value, or a VLAN.
3. Use the “Policy Map” to designate a policy name for a specific manner
in which ingress traffic will be handled.
4. Add one or more classes to the Policy Map. Assign policy rules to each
class by “setting” the QoS value to be assigned to the matching traffic
class. The policy rule can also be configured to monitor the average
flow and burst rate, and drop any traffic that exceeds the specified rate,