The ePMP platform supports three QoS priority levels (not available in ePTP Master mode) using air fairness, priority-based starvation avoidance scheduling algorithm.
Ordering of traffic amongst the priority levels is based on a percentage of total link throughput. In other words, all priorities receive some throughput so that low priority traffic is not starved from transmission. In effect, the greatest amount of throughput is guaranteed to the VOIP priority level, then High, then Low.
|
Priority Level |
ePMP Traffic Priority Label |
|
Highest Priority |
VOIP (only utilized when VOIP Enable is set to Enabled) |
|
Medium Priority |
High |
|
Lowest Priority |
Low |
By default, all traffic passed over the air interface is low priority. The SM’s Quality of Service page may be utilized to map traffic to certain priority levels using QoS classification rules. The rules included in the table are enforced starting with the first row of the table.
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Caution Each additional traffic classification rule increases device CPU utilization. Careful network traffic planning is required to efficiently use the device processor. |
The ePMP platform also supports radio data rate limiting (Maximum Information Rate, or MIR) based on the configuration of the MIR table. Operators may add up to 16 MIR profiles on the AP, each with unique limits for uplink and downlink data rates. The SM field MIR Profile Setting is used to configure the appropriate MIR profile for limiting the SM’s data rate.
|
Attribute |
Meaning |
|
Maximum Information Rate (MIR) |
|
|
MIR Profile Number |
Configure the desired MIR (Maximum Information Rate) profile for SM operation. This profile must be configured on the AP else the default profile (0) is used. |
|
Traffic Priority |
|
|
Traffic Priority |
Enabled: The QoS Classification Rules table is editable and is utilized by the device to classify traffic. Disabled: The QoS Classification Rules table is greyed-out and all traffic is sent at one priority level. |
|
VoIP Priority |
Enabled: When enabled, two entries are automatically added to the first and second rows of the QoS Classification Rules table, one with Rule Type CoS (5) and one with Rule Type DSCP (46). The addition of these rules ensures that VoIP traffic passed over the radio downlink is given highest priority. The CoS and DSCP values may be modified to accommodate non-standard VoIP equipment. |
|
Broadcast Priority |
Low Priority: All Broadcast traffic sent over the uplink is prioritized as low priority and is delivered to the AP after scheduled high priority and VoIP traffic. High Priority: All Broadcast traffic sent over the uplink is prioritized as high priority and is scheduled for delivery to the AP before low priority traffic but after VoIP traffic. |
|
Multicast Priority |
Low Priority: All Multicast traffic sent over the uplink is prioritized as low priority and is delivered to the AP after scheduled high priority and VoIP traffic. High Priority: All Multicast traffic sent over the uplink is prioritized as high priority and is scheduled for delivery to the AP before low priority traffic but after VoIP traffic. |
|
Subscriber Module Priority |
Normal: SM gives priority to the packets as defined in the rules which could be "Low", "High", or "VoIP". "Normal" priority will allow data to be added to the appropriate "High", "Low", and "VoIP" queues based on the QoS rules. This is the default setting. If no rule is defined for a packet, then the packet priority will be “Low”. High: SM places all data other than VoIP in the "High" queue. It will be given higher priority than SMs configured with “Low” and “Normal” when there is contention for bandwidth under the AP. Low: "Low" priority will place all data that is not VoIP in "Low" priority queue. It will be given lower priority than SMs configured with “High” when there is contention for bandwidth under the same AP. "VoIP" queue is the highest priority queue followed by "High" queue and then by "Low" queue. Higher priority queues have preference over lower priority queues, but will not starve them. |
|
QoS Classification Rules |
The QoS Classification Rules table contains all of the rules enforced by the device when passing traffic over the radio downlink. Traffic passed through the device is matched against each rule in the table; when a match is made the traffic is sent over the radio link using the priority defined in column Traffic Priority. |
|
Type |
DSCP: Differentiated Services Code Point; traffic prioritization is based on the 6-bit Differentiated Services field in the IP header present in the packet entering the Ethernet port. CoS: Class of Service; traffic prioritization is based on the 3-bit header present in the 802.1Q VLAN-tagged Ethernet frame header in the packet entering the SM’s Ethernet port. VLAN ID: Traffic prioritization is based on the VLAN ID of the packet entering the SM’s Ethernet port. EtherType: Traffic prioritization is based on 2 octet Ethertype field in the Ethernet frame entering the SM’s Ethernet port. The Ethertype is used to identify the protocol of the data in the payload of the Ethernet frame. IP: Traffic prioritization is based on the source and/or destination IP addresses of the packet entering the SM’s Ethernet port. A subnet mask may be included to define a range of IP addresses to match. MAC: Traffic prioritization is based on the source and/or destination MAC addresses of the packet entering the SM’s Ethernet port. A mask may be included to define a range of MAC addresses to match. The mask is made up of a hex representation of a series of 1s to start the mask and 0s that end the mask. A 1 may not follow a 0. Thus, FF:FF:FF:FF:00:00 is allowed, but FF:00:FF:FF:FF:FF is not. The MAC address is combined with the mask to define the range of allowed MAC addresses. |
|
Details |
The Rule Details column is used to further configure each classification rule specified in column Rule Type. |
|
Priority |
High: Traffic entering the SM’s Ethernet port is prioritized as “high priority” for sending over the radio link (traffic will be sent after VOIP-classified traffic, but before Low-classified traffic). Low: Traffic entering the SM’s Ethernet port is prioritized as “low priority” for sending over the radio link (traffic will be sent after VOIP-classified and High-classified traffic is sent). |