GSM Series User Manual

3-5. QOS (Quality of Service)

The switch offers powerful QoS functions including: Per Port Priority where you can set each port with a different priority level, VLAN tagged priority for 8 levels, TOS field IP header (equal DSCP low 3 bits) on Layer 3 network framework, 6 types of layer 4 network transmission events, and IP DiffServe QoS services.

In the Quality of Service (QoS) Configuration management interface there is an option named ”Default Class”. Once you have selected one of the five QoS methods, this Default Class is used to group packets that do not match any of the QoS rules defined for the particular QoS method selected. For instance, if you set the QoS function as VLAN Tag Priority mode, and then choose Default Class as High, the priority of the packets with no tags will be considered as High priority precedence. The initial value of the Default Class is 'High'.

Fig. 3-19

Function Name:

Per Port Priority

Function Description:

The GSM Series switches allow the administrator to configure High and Low priority levels to individual ports on the switch. For instance if port 1 is set to High priority and port 2 is set to Low priority and both ports are transmitting data at 1G to port 5, packets transmitted from port 2 will be dropped if there is congestion in the switch. Packets will be dropped from port 2 because of the lower priority level than port 1.

Parameter Description:

Port:

Select the port which you would like to set a High or Low priority level to.

Class:

Each port can have a Low or High priority level set.

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Alloy Computer Products GSM-24T2SFP, GSM-8T16SFP, GSM-16T2SFP user manual QOS Quality of Service, Port, Class