Hi, I am doing a research project on clock syncronization using ntp, pcap and tsc. Hopefully the outcome will be a very accurate and robust difference clock. One thing is really bothering me though. I need to have a timestamp that I am SURE of being BEFORE (but very very close to) the NTP packet was sent.
Please pick one or two or all to answer: *How does pcap timestamp outbound packets? (Is it doing a copy of the packet, timestamping it and then send it, or is it somehow sent and then timestamped?) *How accurate is the pcap timestamp (scheduling errors etc)? Is there big accuracy differences between different OS (BSD and Linux). Can I use sigfigs for this? How do I access sigfigs from what I get from pcap_next? *Is there any way of knowing what tsc was when the software clock timestamp was made? Regards, Erik Corell - This is the tcpdump-workers list. Visit https://lists.sandelman.ca/ to unsubscribe.
