Differentiated Services - NETGEAR GSM7252PS - ProSafe 52 Ports Gigabit Ethernet L2 Managed Stackable Switch User Manual

ProSafe® Gigabit L3 Managed Stackable Switches Software Administration Manual
To configure CoS queue settings for an interface:
1. Select the check box next to the port or LAG to configure. You can select multiple ports
and LAGs to apply the same setting to the selected interfaces. Select the check box in
the heading row to apply a trust mode or rate to all interfaces.
2. Configure any of the following settings:
• Queue ID - Use the menu to select the queue to be configured (platform based).
• Use Minimum Bandwidth to specify the minimum guaranteed bandwidth allotted to
this queue. Setting this value higher than its corresponding Maximum Bandwidth
automatically increases the maximum to the same value. Default value is 0. Valid
Range is 0 to 100 in increments of 1. The value 0 means no guaranteed minimum.
Sum of individual Minimum Bandwidth values for all queues in the selected interface
cannot exceed defined maximum (100).
• Use Scheduler Type to specify the type of scheduling used for this queue. Options
are Weighted and Strict. Defining on a per-queue basis allows the user to create the
desired service characteristics for different types of traffic.
• Weighted - Weighted round robin associates a weight to each queue. This is the
default.
• Strict - Services traffic with the highest priority on a queue first.
3. Queue Management Type displays the Queue depth management technique used for
queues on this interface. This is only used if device supports independent settings
per-queue. Queue Management Type can only be taildrop. All packets on a queue are safe
until congestion occurs. At this point, any additional packets queued are dropped.
4. Click Cancel to cancel the configuration on the screen and reset the data on the screen to
the latest value of the switch.
5. If you make changes to the page, click Apply to apply the changes to the system.

Differentiated Services

The QoS feature contains Differentiated Services (DiffServ) support that allows traffic to be
classified into streams and given certain QoS treatment in accordance with defined per-hop
behaviors.
Standard IP-based networks are designed to provide "best effort" data delivery service. "Best
effort" service implies that the network delivers the data in a timely fashion, although there is
no guarantee that it will. During times of congestion, packets may be delayed, sent
sporadically, or dropped. For typical Internet applications, such as e-mail and file transfer, a
slight degradation in service is acceptable and in many cases unnoticeable. Conversely, any
degradation of service has undesirable effects on applications with strict timing requirements,
such as voice or multimedia.
Defining DiffServ
To use DiffServ for QoS, the Web pages accessible from the Differentiated Services menu
page must first be used to define the following categories and their criteria:
Chapter 5. Configuring Quality of Service | 407