Buffer control

Using a large buffer to absorb jitters will stop voice intermittence even when there is jittering. As a side effect, however, there is larger latency. A smaller buffer means less latency, but more chance of intermittence.

As a result, we decided to use an extremely large buffer to absorb jitters and change the size of the buffer depending on the amount of jittering. This allows communication with hardly any latency, given the right network conditions. Voice can be played back without intermittence even if jitters increase and latency occurs.

Here's an example. There is high communication traffic of 10 minutes immediately before the end of business hours, causing increase in jittering. During the other hours, however, there is hardly any jittering. With the buffer control method, communication is possible without latency during the hours other than the 10 minutes prior to closing of business hours. Even during the 10 minutes, continuity of communication is guaranteed despite the presence of latency. One might think 10 minutes during a 24-hour period is less than 1% of the total. However, poor deterioration in quality during the mere 10 minutes may cause major complaints and VoIP would never be used again in place of a telephone. We made repeated assessments using real environments with this firmly in our minds.