The VoIP test assesses the Jitter and Packet Loss for a connection at any given time and also provides details on SIP reponses, SIP ALG and MOS scores.
The MyVoIP test performs jitter and packet loss tests for the connection.
The screenshot below also shows the SIP ALG METRICS, shown towards the bottom of the white box.
SIP ALG stands for Application Layer Gateway, and is common in many commercial routers. It intends to prevent some of the problems caused by router firewalls by inspecting VoIP traffic (packets) and if necessary modifying it. This test DETECTS the presence of this feature.
Both criteria are plotted separately.
The graph tab plots the upstream/downstream jitter & packet loss. The arrows to the left and right of the graph can be used to switch between the two graphs.
The RTT (Round Trip Time) tab, shown on the right, plots the reponse times in a bar chart view for each of the packets sent out during the test.
The Summary tab gives you an overview of the VoIP results. The circular colored indicators are designed to give you a quick understanding of how the test went, in the case shown above you can tell that the VoIP results are considered good.
What is an MOS Score? - The MOS, or Mean Opinion Score, is a numeric measure used for VoIP, indicating the sound quality at the receiving end of a communication circuit. Although the score is subjective it provides a widely-used method to rate the quality of voice communication in a simple way that meaningful to end users. The score is normally between 1 and 5 with 5 being the best.