Quality Of Service - Interlogix GE-DS-242-PoE User Manual

Chapter 6: Command Line Interface

Quality of Service

There are four transmission queues with different priorities in the Managed
Switch: Highest, SecHigh, SecLow and Lowest. The Managed Switch will take
packets from the four queues according to its QoS mode setting. If the QoS
mode was set to "Disable", the Managed Switch will not perform QoS on its
switched network. If the QoS mode was set to "High Empty Then Low", the
Managed Switch will never exhaust packets from a queue until the queues with
higher priorities are empty. If the QoS mode was set to "weight ratio", the
Managed Switch will exhaust packets from the queues according to the ratio. The
default value of QoS mode is "weight 8:4:2:1." That means the switch will first
exhaust 8 packets from the queue with highest priority, and then exhaust 4
packets from the queue with second high priority, and so on.
When the switch received a packet, the switch has to decide which queue to put
the received packet into. In the Managed Switch, it will put received packets into
queues according to the settings of "802.1p Priority" and "Static Port Ingress
Priority." When the received packet is an 802.1p tagged packet, the switch will
put the packet into a queue according to the 802.1p Priority setting.
Otherwise, the switch will put the packet into a queue according the setting of
Static Port Ingress Priority.
 802.1p Priority: the 802.1p packet has a priority tag in its packet header. The
range of the priority is 7~0. The Managed Switch can specify the mapping
between 802.1p priority and the four transmission queues. In the default
setting, the packets with 802.1p priority 0~1 are put into the queue with lowest
priority, the packets with 802.1p priority 2~3 are put into queue with second
low priority, and so on.
 Static Port Ingress Priority: each port is assigned with one priority 7~0. The
priority of the packet received from one port is set to the same priority of the
receiving port. When the priority of the received packet was determined, the
packet is treated as an 802.1p packet with that priority and will be put into a
queue according to the 802.1p Priority setting.
QoS Configuration
QoS mode:
 First Come First Service: The sequence of packets sent is depending on
arrive orders.
 All High before Low: The high priority packets sent before low priority packets.
164 GE-DS-242-PoE Managed Ethernet Switch User Manual