User's Manual

Base Station Configuration Tsunami MP.16 3650 System User Guide
Service Class Creation
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• Service Flows, including their direction and QoS traffic scheduling mechanism(s)
• Networking Parameters, including VLAN properties.
Packet Identification Rules
PIRs are rules that are matched against fields of incoming packets for the purpose of mapping the packet onto the
appropriate service flow. A PIR includes one or more of eleven different classifier fields, which, if included, are matched
against the incoming packet. If a PIR includes multiple classifiers, every included field must match the incoming packet
for the rule to match. The only parts of the packet that are inspected are those corresponding to classifiers included in the
PIR.
PIRs are extremely flexible and can be used In many different ways. Some examples include:
• Using the ToS field in a classification rule to identify a certain class of differentiated IP traffic. This then could be used
to map from the layer 3 QoS to the underlying 802.16 service flow providing the necessary QoS guarantees.
• Using the destination IP address field to identify uplink traffic destined to a particular server address, such as a VoIP
gateway. This could be used to identify VoIP traffic and map it to the appropriate service flow.
A priority is used when assigning a PIR to a Service Flow during SS Class configuration (as described in Step 2:
Associate PIRs with Service Flows later in this guide). This priority is used to filter traffic, with higher priority PIRs being
serviced first. PIR priority is not used per Service Flow on the BS, so unique PIR priority values across all SS Classes are
required to ensure proper traffic prioritization.
Service Flows
As PIRs determine which traffic gets directed to which Service Flow, the Service Flows, in turn, determine the traffic’s
QoS treatment.
The SF direction specifies whether the service flow is to be used by uplink (to the BS) or downlink (from the BS) traffic.
•An uplink service flow is intended for traffic flowing from an SS to the BS.
•A downlink service flow is intended for traffic flowing from a BS to an SS.
SF Quality of Service (QoS)
The SF’s QoS traffic scheduling settings define the method by which bandwidth is allocated for packets sent over that
service flow.
Quality of Service (QoS) for networks is an industry-wide set of standards and technologies for ensuring high-quality
performance for critical applications. By using QoS mechanisms, network administrators can use existing resources
efficiently and ensure the required level of service without reactively expanding or over-provisioning their networks.
Traditionally, the concept of quality in networks meant that all network traffic was treated equally. The result was that all
network traffic received the network’s best effort, with no guarantees for reliability, delay, variation in delay, or other
performance characteristics. With best-effort delivery service, however, a single bandwidth-intensive application can
result in poor or unacceptable performance for all applications. The QoS concept of quality is one in which the
requirements of some applications and users are more critical than others, which means that some traffic needs
preferential treatment.
The goal of QoS is to provide preferential delivery service for the applications that need it by ensuring sufficient
bandwidth, controlling latency and jitter, and reducing data loss, while also making sure that providing priority for one or
more flows does not make other flows fail.
QoS lets you provide better service to certain flows of traffic. This is done by either raising the priority of a flow or limiting
the priority of another flow. You can raise the priority of a flow by queuing and servicing queues in different ways:
• Raise priority by dropping lower-priority flows before higher-priority flows.
• Police and shape priority to a flow by limiting the throughput of other flows.