Each Accolade ANIC SmartNIC can perform nanosecond precision timestamping. But as the famous adage goes: “garage in, garbage out”. In other words, timing precision is only as good as the timing source one utilizes. Put another way, each ANIC adapter must be “disciplined’ by some timing source in order to timestamp packets. The level of required time precision will dictate how the ANIC adapter is disciplined. For example, if you don’t really care about timing precision then the easiest thing to do is let the adapter be disciplined by the host operating system (e.g. Linux). This will be a relatively coarse level of precision but for most applications this is adequate. In fact, host OS disciplining is by far the most common method.
On the opposite end of the spectrum are customers that require very precise timestamping, for example, those that are performing very fine-grained forensic security. If the timestamp is not precise, the host application may incorrectly sequence packets and not be able to determine in which order a specific malicious activity occurred. For these timestamping needs, customers typically hook up an external timing source to the adapter via the mini-coax port on the front. The provided external signal is known as “1PPS” or “1 Pulse-Per-Second” and is most often supplied via GPS or the cell phone network.
For more information on ANIC adapter features, download the overview below.