Cisco PORT QOS MIB - Overview
This MIB module is for the management of Cisco's
per port rate-limiting and traffic shaping on L3
Per-port rate-limiting is a traffic control method.
A set of rate limits are applied to the traffic
traversing an interface. Each rate limit has a
configurable action that is taken when rate
limiting criteria is met.
Per-port traffic shaping is a traffic control
method. The user can restrict the amount of traffic
coming out of a physical port. Excess traffic is
buffered within the router/switch to the extent
A class represents a class of traffic. It is defined
via the specification of the packet matching criteria
that identifies packets that are to belong to the class.
Class-default: In addition to user defined classes,
a pre-existing class named 'class-default' exists to
represent all packets that do not match any of the user
defined classes. This class-default exists so that
policies can be defined for this group of packets that
do not match any user defined classes.
Actions are individual policies (e.g.: policing) that
can be applied to a traffic class.
A policy represents a set of actions that are to be
applied to a set of traffic classes. The policy is
associated with a target (like a port) and the direction
of traffic on that target to which the policy is to be
A hierarchical policy is one in which an entire policy
is directly assigned to a class of traffic. Thus, a
hierarchical policy is a nested policy that contains
a set of the pair of a child-policy and the
traffic-class to which it is applied.
DSCP (Differentiated Services Code Point) is the six
most significant bits of the ToS field in a IP packet
CoS (Class of Service) is the three bits in the layer 2
header that indicates user priority value assigned to
This MIB module also provides per port QoS statistics.