FMADIO Push PCAP has the ability to extract and overwrite the timestamp presented in the PCAP. By deafult the timestamp in the PCAP is what the FMADIO FPGA Timestamp is, however this can be sub-optimial as the TapAggregation layer prior to the capture introduces timming jitter due to store-and-foreward.
Splitting
FMADIO Push PCAP always uses the FMADIO FNIC FPGA timestamp to split the traffic.
In firmware version prior to 2026 Q2 release, the split logic may have used the packet brokers timestamp. This has been removed as the splitter requires a stable monotonically increasing timestamp, on ALL PACKETS. For example if stray switch to switch traffic or packets missing the packet brokers header/footer arrive, the current time vs new time may be a discrtete jump (forward or backward). This jump can cause significant disruption as the file splitter linear forward time. As such the spliter uses the FMADIO FNIC timestamp to ensure maximum robustness with the PCAP splitter.
Filename vs Packet Time
When the PCAP Packet time is overwritten by the PacketBrokers timestamp (e.g. Arista 7130 footer), this behavior of using the FMAD FNIC timestamp for file boundaries, may cause discrepancies between the filename of the PCAP vs whats seen on the first packet in a PCAP. The only solution is to ensure the FMAD Appliance and the Packet Broker are both disciplined by the same time master.