Packet Timing/Recovery Analysis
- Eli Pielet (Writec) (Unlicensed)
Packet timing analysis displays a histogram of packet arrival time, including recovered packets, from Push and Pull Sources. This analysis can be used to see a history of latency from the Source and to fine tune latency targets. In the graph, the vertical axis is time in milliseconds with the max value set to the latency target and the horizontal axis is user specified minutes, hours, days, etc. Darker red in the histogram means more packets arrive at that particular latency. In the graph below, most packets arrived under 1 second but some arrived just over 1 second. Since the target latency was set to 4 seconds, FEC in the Zixi algorithm would have been essentially disabled because the round trip time relative to the target latency was short enough to recover dropped packets. Looking at the historical data, it would be reasonable to set the target latency around 1 second and then the dynamic use of FEC in the Zixi protocol would be used occasionally, when necessary. Setting a latency target of 500ms under these network conditions would not be reasonable due to the inherent latency of the network connection.
