Packet Delay
Monitor Packet Delay and Improve VoIP Quality with PRTG
For interactive real-time applications such as VoIP, packet delay can be a serious issue. With PRTGNetwork Monitor, you can monitor quality of service parameters like packet delay, packet loss, duplicate packets and network latency and take the appropriate steps to improve VoIP quality.
How Does Packet Delay Affect VoIP Quality?
In contrast to normal telephone service, which is based on a circuit-switching technology, VoIP telephony uses packet switching for transmitting voice messages. This means that messages are divided into packets before they are sent. Some of these packets might be delayed or even lost, which can lead to poor voice quality or noise.
What Is Packet Delay?
Packet delay is the amount of time it takes for a packet to travel from end to end. So a certain packet delay is perfectly normal. If the delay is rather short (for good voice quality, end-to-end packet delay should not be bigger than 150 ms) and constant, VoIP quality is not affected. VoIP quality is adversely affected when a considerable packet delay variation occurs, i.e. some packets arrive much later than the rest. Packet delay variation is often called jitter and can cause echo in VoIP calls. Packet delay depends on many different factors, among others the underlying network and available net bandwidth.
PRTG Network Monitor
PRTG Network Monitor has a dedicated QoS sensor, which works by sending UDP packets between two remote probes. This means that you can test any network connection in your network by simply placing a remote probe on (or near) each "end" of the connection and measuring the connection quality between them. If the network monitor detects a problem, the administrator is notified immediately and can react quickly and effectively. Thus PRTG is the perfect VoIP monitoring software as it finds network issues that can affect VoIP sound quality (packet delay, jitter, packet loss).
However, PRTG Network Monitor is far more than a VoIP monitoring manager. PRTG is a powerful bandwidth and availability monitoring solution which helps you to keep control of your network. It mainly uses the network management protocol SNMP, but also packet sniffing and supports the NetFlow / xFlow protocol and IP-SLA monitoring. PRTG is available as fully functional 30-day trial license and Freeware Edition, which is completely free for personal and commercial use. The Commercial Editions are required to monitor more than 10 sensors, with licenses starting at just $400 / €300.
