Understanding Quality of Experience

Quality of Experience (QoE) is a dashboard within Orion that allows you to monitor traffic on your network. QoE uses Packet Analysis Sensor to provide packet-level traffic information about key devices and applications that you specify.

With Quality of Experience, you can:

  • Compare statistics like network response time (TCP Handshake) and application response time (Time to First Byte) to determine if a perceived bottleneck is actually on your network, or if you need to call the server team.
  • Use data volume trends to pinpoint traffic anomalies and investigate the cause.
  • Monitor "risky" types of traffic.

There are three steps you must complete to start monitoring traffic on your network:

  1. Deploy Packet Analysis Sensors (network and/or server) to Windows nodes where you want to collect traffic data.
  2. In the web console, specify the nodes and applications for which you want to collect traffic.

    Packet Analysis Sensors do not automatically discover nodes and applications. You must indicate the nodes and applications to monitor before you see traffic data in the web console.

  3. Allocate appropriate CPU cores and memory for the traffic load for each sensor.

Traffic data is captured using packet analysis sensors. These sensors collect packets using either a dedicated Windows SPAN or Mirror port monitor or directly on your Windows server. Packet Analysis Sensors capture packets from the local network interface (NIC) and then analyzes collected packets to calculate metrics for application performance monitoring. These metrics provide information about application health and allow you to identify possible application performance issues before they are reported by end-users.

With the ability to analyze packet traffic, QoE provides real observed network response time (NRT) and application response time (ART). In addition, Packet Analysis Sensors have the ability to classify and categorize traffic for over 1000 different applications by associated purpose and risk-level.

User Scenarios

The following scenario serves as an example of how sensors can monitor network performance.

Scenario: High Response Time

A web server is providing an important web application. Your users are encountering response times that are too long and also encountering outages.

Use the following procedure to troubleshoot the high response time issue:

  1. Remotely deploy a Server sensor directly on the web server.
  2. Define which application(s) should be monitored, and let the data be collected for a period of time to establish some trends.
  3. Determine if the issue is on the network side or if there is a problem with the application.
  4. Check related statistics and historical data.

Configuring Nodes and Applications to Monitor

After you have deployed Network and Server sensors, you must specify the nodes and applications whose traffic you want to monitor. QoE does not automatically discover nodes or applications.

  • You must specify which nodes and applications you want the network sensors to monitor before traffic for these nodes can be collected and data appear in the QoE dashboard.
  • Server Sensors automatically monitor pre-selected applications-including CIFS, FTP, HTTP, MS SQL, RDP, and SNMP-on the node they are installed on. You can change which applications are monitored after the sensor is deployed.

For each node you choose to monitor, you must also select specific applications. Packet Analysis Sensors can categorize over 1,000 predefined applications, such as FTP, RDP, CIFS, SQL, and Exchange. You can also define your own custom HTTP applications.

Because of the hardware requirements needed to process large amounts of traffic, SolarWinds recommends that you preferentially monitor business-critical nodes and applications. You can monitor up to 50 applications per node.

Advanced Sensor Configuration

Sensors cannot be edited until they are fully deployed. You are notified when your sensor is deployed, or you can check the Manage QoE Nodes page. The status of completely deployed sensors is Connected.

You can configure:

  • The monitored interface
  • The allocated CPU cores and memory

Packet Analysis Sensor Agents

The software that provides a communication channel between your SolarWinds server and the monitored object to which you have deployed your Packet analysis Sensor is referred to as the agent. Agents are used to provide packet-level traffic information about key devices and applications that you specify. The agent runs as a service on Windows 2008, Windows 2008 R2, and Windows 2012, and it has a relatively small footprint (under 100MB installed).

For more information, see Managing Quality of Experience