Juniper JUNOSE 11.1.X - QUALITY OF SERVICE CONFIGURATION GUIDE 3-21-2010 Configuration Manual page 38

JUNOSe 11.1.x Quality of Service Configuration Guide
Table 3: QoS Terminology (continued)
6
QoS Terms
Term Description
Effective weight The result of a weight or an assured rate. Users configure the
scheduler node by specifying either an assured rate or a weight
within a scheduler profile. An assured rate, in bits per second, is
translated into a weight. The resultant weight is referred to as an
effective weight.
Group node A scheduler node associated with a {port interface, traffic-class
group} pair. Because the logical interface is the port, only one such
scheduler node can exist for each traffic-class group above the port.
This node aggregates all traffic for traffic classes in the group.
HAR Hierarchical assured rate. Dynamically adjusts bandwidth for
scheduler nodes.
HRR Hierarchical round-robin. Allocates bandwidth to queues in
proportion to their weights.
Latency Delay in the transmission of a packet through a network from
beginning to end.
Proprietary QoS Supported on the E Series router.
Management Information
Base (MIB)
Queue First-in-first-out (FIFO) set of buffers that control packets on the data
path.
QoS port-type profile Supplies the QoS information for forwarding interfaces stacked above
ports of the associated interface type.
QoS profile attachment Applies the rules in the QoS profile to a specific interface.
Rate shaping Allows you to throttle a queue to a specified rate.
RED Random early detection congestion avoidance technique.
Scheduler hierarchy A hierarchical, tree-like arrangement of scheduler nodes and queues.
The router supports up to three levels of scheduler nodes stacked
above a port. The port scheduler is at level 0, with two levels of
scheduler nodes at levels 1 and 2. A final level of queues is stacked
above the nodes.
Scheduler node An element within the hierarchical scheduler that implements
bandwidth controls for a group of queues. Queues are stacked above
scheduler nodes in a hierarchy. The root node is associated with a
channel or physical port.
Shaping rate Bandwidth in a queue or node can be throttled to a specified rate.
Shared shaper constituent All nodes and queues that are associated with a logical interface that
is being shared shaped are considered potential constituents of the
shared shaper.
Weight Specifies the relative weight for queues in the traffic class.