Assumptions

The following assumptions apply to timestamps.

• All timestamps are created by the DNCA software at the point of capture. When the software sees data at its capture point, it then assigns a timestamp.
• The DNCA host machine is a short, negligible distance from the HTTP generating source. However, this factor must not impact the timestamps, since data typically flows unimpeded from the web server to the client.
• Data is sent as fast as the end-to-end network path permits. There are potential issues that can affect the timestamp accuracy of the traffic that is arriving at the DNCA. If the capture point is a switch span port, the internal buffers that are used to aggregate the span traffic can change its real-time data arrival. Buffers can hold and burst the span port traffic at any time that impacts the accuracy. Other network devices can also change the data arrival times if it's part of the capture traffic path but not in the live traffic path.
• All timestamps are specified in GMT with microsecond granularity. A microsecond is one-millionth of a second.