Calculating network performance metrics

A transaction is defined as a client request followed by a server reply, including both TCPTransmission Control Protocol and UDPUser Datagram Protocol flows. With each read and write transaction between a client and a server, the following values are measured and used to calculate how long the transaction takes to complete:

  • Round Trip Time — the time taken for a very small packet to travel across the network and return
  • Network Delay— the overall time taken for data to cross from a client to a server, or from the server to a client.
  • Server Delay— the time taken for a server to respond to a request.
  • Total Transaction Delay— The time taken for data to cross the network from a client to the server and back. Unlike round trip time, this could include large packets and could result in multiple packets being sent to the server, or received from the server.
  • Network Jitter— measures the variability of the network delay time. This is expressed as a multiple of one standard deviation.
  • Packet Loss— measures when one or more packets within a transmission are successfully sent, but fail to arrive at the destination.

Refer to these topics for more information: