# Response Time Aggregation

> How an agent aggregates response time measurements per server and TCP port within a report period.

Source: https://docs.capaone.com/performanceguard/technical-reference/concepts/response-time-aggregation/  
Product: PerformanceGuard — a separate CapaSystems product; do not apply this page to any other.

An agent aggregates response time measurements based on the server and TCP port with which the client communicates. For example, for response times for all communication with a specific web server within a single report period, the following is reported to the backend :

- Accumulated response time
- Number of connections
- Number of trains sent and received (for more information about trains see [TCP IP](/performanceguard/get-started/how-does-performanceguard-work/tcp-ip/)).
- Number of bytes sent and received

The response time for that combination of \<agent, server, service\> is then calculated by the backend as the accumulated response time divided by the number of received trains.

In order to show response times from measurements taken on multiple clients it's necessary to aggregate the data further. In this case the response time concerning a group of agents and a specific \<server, service\> is calculated as the sum of accumulated response times divided by the sum of received trains for all agents in the group.