Gigabit Ethernet Packet Capture User's Guide - messkom.de
Gigabit Ethernet Packet Capture User's Guide - messkom.de
Gigabit Ethernet Packet Capture User's Guide - messkom.de
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the timestamp mo<strong>de</strong> that best suits your needs, from highly accurate<br />
timestamps to no timestamp generation.<br />
Polling Mo<strong>de</strong>. In this mo<strong>de</strong>, a CPU polls for packet arrivals and<br />
timestamps the packet as soon as it is available from the board. These<br />
timestamps are very accurate (microsecond accuracy) but require a CPU to<br />
be running in a busy wait loop.<br />
Timer Mo<strong>de</strong>. Timer mo<strong>de</strong> uses a 1ms timer to periodically timestamp<br />
incoming packets. This puts very little load on the CPU and provi<strong>de</strong>s<br />
timestamps with millisecond accuracy.<br />
Off. In this case, no timestamps are generated and the timestamp fields in<br />
the packet meta-information are set to zero.<br />
Figure 4 - Pass-thru Mo<strong>de</strong><br />
In Figure 4 the first board is selected in the Available Boards box. The<br />
Board ID is shown in the Board Properties box and corresponds to the<br />
MAC address of Port A and is used for i<strong>de</strong>ntification purposes only.<br />
When Pass-thru is enabled, it is important that the negotiated link speeds<br />
on both ports are i<strong>de</strong>ntical. The pass-thru speed is selected from the dropdown<br />
list.<br />
Figure 5 - Editing Port Names<br />
TurboCap User’s <strong>Gui<strong>de</strong></strong> 13