Configuring Quality Of Service - NETGEAR ProSafe FS728TP Software User Manual

FS728TP Smart Switch Software User Manual

Configuring Quality of Service

Quality of Service (QoS) provides the ability to implement priority queuing within a network. For
example, certain types of traffic that require minimal delay, such as Voice, Video, and real-time
traffic can be assigned a high priority queue, while other traffic can be assigned a lower priority
queue. The result is an improved traffic flow for traffic with high demand. QoS is defined by:
• Classification – Specifies which packet fields are matched to specific values. All packets
matching the user-defined specifications are classified together.
• Action – Defines traffic management where packet forwarding is based on packet information
and packet field values such as VLAN Priority Tag (VPT) and DiffServ Code Point (DSCP).
After packets are assigned to a specific egress queue, CoS services can be assigned to the queue.
Egress queues are configured with a scheduling scheme by one of the following methods:
• Strict Priority – Ensures that time-sensitive applications are always forwarded. Strict Priority
(SP) allows the prioritization of mission-critical, time-sensitive traffic over less time-sensitive
applications. For example, under SP, voice over IP (VoIP) traffic can be prioritized so that it is
forwarded before FTP or email (SMTP) traffic.
• Weighted Round Robin – Ensures that a single application does not dominate the device
forwarding capacity. Weighted Round Robin (WRR) forwards entire queues in a round robin
order. All queues can participate in WRR, except SP queues. If the traffic flow is minimal, and
SP queues do not occupy the whole bandwidth allocated to a port, the WRR queues can share
the bandwidth with the SP queues. This ensures that the remaining bandwidth is distributed
according to the weight ratio. If WRR is selected, the following weights are assigned to the
queues: 1, 2, 4, 8.
This section contains information for defining general QoS settings, and includes the following
topics:
• Defining General QoS Settings
• Defining QoS Queues
• Configuring Bandwidth Settings
• Mapping CoS to Queues
• Mapping DSCP Values to Queues
5-87 Configuring the Device Using Your Browser
v2.0, November 2006