Configuring Quality of Service
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management traffic, such as telnet, HTTP, or SNMP that is directed to the router
itself.
Two types of ACLs are defined:
• IP ACL — Applies only to IP packets. All classification fields are related to IP
packets.
• MAC ACL — Applies to any packet, including non-IP packets. Classification fields
are based only on Layer 2.
There are two ways to apply ACLs to an interface:
• Policy — In this form, ACLs are grouped together into a more complex structure,
called a policy. The policy can contain both ACLs and QoS rules. The user can
apply the policy to an interface (see “Advanced QoS Mode”).
• Simple — In the simple form, a single (MAC or IP) ACL is applied to an interface.
Although a policy cannot be applied to an interface, it is possible to apply basic
QoS rules that classify packets to output queues (see “Basic QoS Mode”).
Mapping to Queues
Queues are used in both Basic and Advanced QoS modes. Default settings are
applied to maps in Service QoS mode. A Trust Behavior can be selected, or the
output service fields can be selected, including:
• VLAN Priority Tags (VPT) — VPTs are mapped to an output queues based on the
VPT. While queue mapping is user-configurable, the VPT default mapping to the
output queue is as follows. In the VPT default mapping, Queue 2 has the lowest
priority. The following table contains the VPT to Queue default settings:
Table 3-5. VPT Default Mapping Table
Notes:1. Mapping of the VPT to the output queue is performed on a system-wide
basis, and can be enabled or disabled per port.
2. Packets may egress with a different VLAN Priority Tag than the one with
which they ingressed. A different tag may be applied to the packets. If no
QoS mode is configured, then the VPT for tagged packets remains
unchanged. For untagged traffic, a VPT is assigned. When VPT trust mode
is configured, untagged packets are mapped to the default port VPT.
VPT Value Queue Number
02
11
21
32
43
53
64
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