What Is Delay in VoIP?

VoIP technology smooths over many delays in call transmission

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Voice over Internet Protocol (VoIP) is technology that permits voice communications over the internet using a high-speed internet connection instead of an analog phone line. VoIP services convert your voice into a digital signal that is portioned into packets. The packets travel over the internet to reach the call recipient.

When VoIP Packets Are Delayed

Delay is caused when packets of voice data take more time than expected to reach their destination. This delay, called latency, causes some disruption in the voice quality. However, the VoIP technology is equipped to deal with some delay, so the effects are minimized.

When packets are sent over a network toward a destination computer, IP phone, or VoIP service, some of them might be delayed. Reliability features in the voice-quality mechanism see to it that a conversation is not deadlocked waiting for a packet that didn't arrive on time. Many factors affect the journey of packets from source to destination, and one of them is the underlying network.

The delayed packet may arrive late or may not arrive at all, in which case, it is lost. Quality of Service (QoS) considerations for voice are relatively tolerant toward packet loss, as compared to text. If you lose a word or a zero in your balance, your text might mean something completely different. If you lose a “hu” or a “ha” in a speech, it does not make a huge impact, except some hitch in voice quality. Besides, a voice-smoothing mechanism regulates the call so that you don’t feel the bump.

The Effects of Delayed Packets

When a packet is delayed, you hear the voice later than you should, or you may hear an echo during the call. If the delay is not big and is constant, your conversation can be acceptable. Unfortunately, the delay is not always constant and varies depending on technical factors. This variation in delay is called jitter, which causes damage to voice quality.