Quality of service (QoS) is a capability of an IP network. That is, the capability can provide service required for specified business on the IP network crossing multiple bottom-layer network technologies (such as Ethernet, ATM, SDH, MPLS, MP, and FR). This ensures expected service level at aspects such as packet loss rate, delay, jitter, and bandwidth.

eSight provides QoS Manager to monitor traffic. When traffic policies are configured for interfaces and VLANs, the tool measures network performance counters such as rate of packets matching a traffic classifier, packet drop rate, rate of packets exceeding the CIR, and bandwidth usage for the interfaces.

• You are advised to use the operation process that has been strictly tested. If the non-recommended operation process is used, an unknown exception may occur. In this case, perform operations based on the recommended process.
• For details about the device model and version matching eSight functions and features, see the specification list.
• For precautions on using eSight features, see the information provided on the software GUI and in documents, ensuring that the features can be used normally.
• When modifying the eSight configuration file to change the feature, you must perform operations under the guidance of technical support engineers. Otherwise, unknown errors may occur and eSight may be unavailable.
• Only the CBQoS that applies to the interface and VLAN are supported, but the global CBQoS is not supported.
• Only the CAR, GTS, WRED, and queue can be configured for the CBQoS that applies to the interface.
• Only the CAR, GTS, and queue can be configured for the CBQoS that applies to the VLAN.
• When collecting performance data through QoS, ensure that the traffic statistics function is enabled in the traffic policy or traffic behavior of the device. The command for enabling the function is statistics enable.
• In versions later than V8, the NE series does not support the display of the matching rules of QoS traffic classification on eSight.

By normalizing QoS traffic KPIs (blocking vendor and QoS configuration differences), QoS traffic management of eSight extracts the four QoS traffic KPIs (matching rate, discarding rate, bandwidth usage, and over committed bandwidth rate) concerned by users, reducing the O&M efficiency.

• Matching rate: Reflects the actual traffic volume of each traffic classification, enabling users to learn the actual traffic distribution of each traffic classification.
• Traffic classification bandwidth usage: Indicates the ratio of the actual traffic of the traffic classification to the bandwidth limit of the traffic classification. You can set the threshold of this KPI to implement traffic warning.
• Discarding rate: Reflects the packet loss information of each classification during QoS scheduling. By analyzing the value of this KPI, you can learn the impact of congestion on services (for example, whether packet loss occurs and which traffic classification encounters packet loss).
• Over committed bandwidth rate: Indicates the difference of the actual traffic bandwidth of the traffic classification minus the limited bandwidth of the traffic classification. Through this KPI, you can learn the bandwidth insufficiency information, providing data support for bandwidth adjustment.