Installation guide
Table Of Contents
- Chapter 1: Introduction
- Chapter 2: Initial Configuration
- Chapter 3: Configuring the Switch
- Using the Web Interface
- Navigating the Web Browser Interface
- Web Configuration
- Displaying Status Overview
- Showing Port Statistics
- Displaying the System Name
- Setting the Switch’s IP Address
- Configuring the Logon Password
- Tools
- Register Product
- Port Configuration
- Storm Control
- Port Mirroring
- Cable Diagnostic
- Trunk Membership
- Trunk Configuration
- LACP Setup
- LACP Status
- Configuring VLAN Groups
- 802.1X
- LLDP Settings
- LLDP Neighbor Table
- RSTP
- QoS Settings
- SNMP
- PoE
- Appendix A: Software Specifications
- Appendix B: Troubleshooting
Configuring the Switch
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QoS Settings
QoS (Quality of Service) is a mechanism that is used to prioritize traffic as it is
forwarded through the switch. Both the queue service mode (strict or weighted
round robin), and the method of classifying the priority of ingress traffic can be
configured on this page.
Traffic can be classified as high, medium, normal or low priority. When the switch is
heavily loaded, lower priority traffic is dropped first. You can select how to prioritize
traffic by using one of the QoS modes (none, 802.1p, or DSCP).
Selecting the Queue Mode
You can set the switch to service the queues based on a strict rule that requires all
traffic in a higher priority queue to be processed before lower priority queues are
serviced, or use Weighted Round-Robin (WRR) queuing that specifies a relative
weight of each queue.
Strict priority requires all traffic in a higher priority queue to be processed before
lower priority queues are serviced.
WRR uses a relative weighting for each queue which determines the amount of
packets the switch transmits every time it services each queue before moving on to
the next queue. Thus, a queue weighted 8 will be allowed to transmit up to 8
packets, after which the next lower priority queue will be serviced according to it’s
weighting. This prevents the head-of-line blocking that can occur with strict priority
queuing.
Selecting the Method of Priority Processing
This switch supports several common methods of prioritizing traffic to meet
application requirements. It can process traffic priorities specified by the IEEE
802.1p priority bits in Layer 2 traffic, or the Differentiated Services Code Point
(DSCP) service priority bits found in Layer 3/4 traffic. When either of these services
are enabled, the priorities are mapped to a Class of Service value by the switch, and
the traffic then sent to the corresponding output queue.
If the QoS mode is set to 802.1p, and the ingress packet type is IPv4, then priority
processing will be based on the 802.1p value in the ingress packet. For an untagged
packet, the default port priority is used for priority processing (i.e., CoS value 0,
which maps to the Normal Queue).
If the QoS mode is set to DSCP, and the ingress packet type is IPv4, then priority
processing will be based on the DSCP value in the ingress packet.