Quality Of Service
Introduction
Minimum firmware: 18.4.54
Quality Of Service (QOS) is a feature within the Accelerated Concepts routers to manage traffic performance of different services, such as Voice over IP (VoIP), cloud computing, traffic shaping, traffic prioritizing, bandwidth allocation etc.. The configuration for QOS is included in the Firewall section of the device configurations.
By default, QOS functionality is disabled, however there is a configuration designed for a typical VoIP site defined. The default configuration provides an example of matching packets as they are routed out from the device onto the LAN (labelled inbound) and out from the device on the WAN interface (labelled outbound). It is important to remember when configuring QOS that we can only control the egress packet queue on each interface, not what we receive on the interface (packet ingress).
This article explains the configuration related to QOS on Accelerated devices. Further explanation of each configurable field can be accessed by hovering over the Help button in the small triangle tip next to the field-in-question.
Quality Of Service Configuration
All bindings, policies, and rules are added and configured in Firewall > Quality Of Service. If custom QOS bindings are required, click on Add to add a new binding. The order of the bindings can be sorted by simply dragging on the binding and moving it.
Binding
Each Binding should be uniquely bound to a network interface. A binding contains the policies and rules applicable packets exiting on that interface. Each binding includes the following configurable fields:
| Field |
Description |
|---|---|
| Enable | To enable or disable the binding of interest. |
| Label | Plain text used to name this binding. |
| Interface | The interface to queue egress packets on. The interface is fundamental and we can only match traffic that is being sent out on this interface. |
| Interface bandwidth (Mbit) | The maximum bandwidth of the interface with respect to the direction of traffic flow this binding is defining. It is recommended that a 95% of the maximum interface bandwidth is used in this field. |
| Policy | At least one policy for each binding is required. Each binding policy can contain up to 30 rules. |
Policy
A Policy sets behavioural attributes of the traffic matched by a collection of rules. This is the defining part of the HFSC queue, which regulates packet sending by applying complex algorithms based on the latency and bandwidth available. The rules, or Policy Rules are also defined in the policy. These policies can be added by clicking on Add button next to Add Policy. Each policy includes the following configurable fields:
| Field |
Description |
|---|---|
| Enable | To enable or disable the policy. |
| Label | Plain text used to name the policy. |
| Weight | A portion of the combined policy weights of a binding. The larger the weight (with respect to the other policy weights), the larger portion of the maximum bandwidth is available. For example, if a binding contains three (3) policies, each policy contains a weight of 10. Therefore the traffic matching each policy will be 1/3 of the total interface bandwidth. |
| Latency | The maximum delay in the transmission of related packets. The lower the latency, the faster the packets will be scheduled for transmission. |
| Default | Specifies whether the policy is a fall-back policy, i.e. the policy used for traffic that is not matched by a policy rule. If unchecked, custom policy rules can be defined. It is critical to define a default, otherwise any packets that do not match a rule will be dropped. |
Rule
The Rule specifies the types of packets that will inherit the parent policy's attributes. Rules can be added by first unchecking Default, then click the Add button next to Add Rule. Each rule includes the following configurable fields:
| Field | Description |
|---|---|
| Enable | To enable or disable the rule. |
| Label | Plain text used to name the rule. |
| Type Of Service | A Type Of Service (TOS) value specified in a packet header. A list of common TOS values can be found in this link. If unspecified, this field is ignored. |
| Protocol | The IP protocol matching criteria. It can be TCP, UDP, or ANY other IP protocol. |
| Source port | Source port of the traffic to match. |
| Destination port | Destination port of the traffic to match. |
| Source address | A slide out tab with the option to choose a Type. Apart from Any, each of the options reveals a corresponding drop-down field:
|
| Destination address | A slide out tab with the option to choose a Type. Apart from Any, each of the options reveals a corresponding drop-down field:
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