Moxa EDS-518A-MM-SC [50/109] Configuring traffic prioritization

Moxa Managed Ethernet Switches Featured Functions

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Traffic Queues

The hardware of Moxa switches has multiple traffic queues that allow packet prioritization to occur. Higher

priority traffic can pass through the Moxa switch without being delayed by lower priority traffic. As each packet

arrives in the Moxa switch, it passes through any ingress processing (which includes classification,

marking/re-marking), and is then sorted into the appropriate queue. The switch then forwards packets from

each queue. Moxa switches support two different queuing mechanisms:

• Weight Fair: This method services all the traffic queues, giving priority to the higher priority queues.

Under most circumstances, the Weight Fair method gives high priority precedence over low priority, but in

the event that high priority traffic does not reach the link capacity, lower priority traffic is not blocked.

• Strict: This method services high traffic queues first; low priority queues are delayed until no more high

priority data needs to be sent. The Strict method always gives precedence to high priority over low priority.

Configuring Traffic Prioritization

Quality of Service (QoS) provides a traffic prioritization capability to ensure that important data is delivered

consistently and predictably. The Moxa switch can inspect IEEE 802.1p/1Q layer 2 CoS tags, and even layer 3

TOS information, to provide a consistent classification of the entire network. The Moxa switch’s QoS capability

improves your industrial network’s performance and determinism for mission critical applications.

IEC 61850 QoS

IEC 61850 QoS (Quality of Service) is an application-based communications prioritization function that can

prioritize critical messages, which are sent with the GOOSE/SMV/PTP protocols in power substations. In

comparison, QoS Classification can only use port-based message prioritization.

Supported Models

PT-7728 series, PT-7828 series, PT-7728-PTP series (Firmware V3.4)

Enable Packet Priority

Setting Description Factory Default

Enable IEC 61850 QoS Enable or disable IEC 61850 QoS functionality Disable

GOOSE

Setting Description Factory Default

High/Medium/Normal/

Low

The priority sequence is High>Medium>Normal>Low. We

recommend setting GOOSE packets to high priority.

High