Jitter Buffer
A temporary memory buffer that smooths out variations in packet arrival times to prevent choppy or distorted audio in VoIP calls.
When voice data travels over the internet, it is broken into small packets and transmitted independently. Due to network variability, these packets don't always arrive at their destination in the same order or at the same intervals — this variation in arrival timing is called jitter. Without compensation, jitter causes audible distortion: choppy audio, robotic speech, or gaps in conversation.
A jitter buffer holds incoming voice packets briefly in a temporary memory store, reorders them if necessary, and releases them to the audio decoder in a smooth, consistent stream. The buffer absorbs the timing variations before they reach the speaker, making the audio sound continuous even when the network is delivering packets unevenly.
Jitter buffers are either fixed (always hold packets for a set delay) or adaptive (dynamically adjust the buffer size based on real-time network conditions). Adaptive jitter buffers are preferred in modern VoIP systems because they minimize overall delay while still handling most network variability. High jitter — typically above 30–40ms — indicates network instability and can cause call quality problems even with a well-configured jitter buffer. Zonitel's infrastructure monitors jitter levels in real time and routes calls over the lowest-latency available path.