The first two graphs visualize overall 'Delay' for each direction experienced by a packet including the serialization time -- the bandwidth and packet length dependent time needed by the ingress device to receive the whole packet. The other two graphs show 'Processing Delay' -- Delay minus serialization time. The basis for these delay calculations are Dag timestamps. Packets from two trace files are matched by calculating and comparing 64-bit CRCs for each packet. The CRCs are calculated over the first 40 bytes of each IP packet excluding IP header checksum and TTL.
To handle different amounts of delay values in one graph, points are randomly dropped so that only approximately 400 data points are plotted for each 60 second-bin.
To illustrate packet length dependencies, each point is colored according to the length of the represented IP packet. We distinguish six length groups: 40, 41-51, 52,, 53-575, 576, 577-1499, and 1500. Note that these groups were chosen to represent prevalent length values of 40, 576, and 1500 bytes.
| Source Packets | Dest. Packets | Matches | Unmatched Source Packets | Unmatched Dest. Packets | Duplicate Source Packets | Duplicate Dest. Packets |
|---|---|---|---|---|---|---|
| 169224171 | 171560995 | 166178757 | 782938 | 177718 | 2177936 | 5187139 |
Last updated: Klaus Mochalski