Device and method for determining a voice transmission delay over a packet switched network

摘要

A direct way to measure network delay of a packet switched network uses a ping signal injected into the voice stream at a source telephone. The ping signal travels together with the voice stream to a destination telephone. The destination telephone detects the ping signal and returns it to the source telephone through the packet switched network. The source telephone detects the return ping signal sent by the destination telephone and calculates the network delay between the two telephones based on the difference between the time of transmitting the ping signal and the time of detecting the return ping signal. As the ping signal travels in the same path as the voice stream, the network delay between the two telephones is calculated directly and accurately.