RE: Ping Function

From: swjhes@mgtlimited.com
Date: Wed May 23 2001 - 14:30:42 EEST

  • Next message: Craig Small: "Re: How do I make a dummy AX.25 interface?"

    Comments follow:

    > One way of doing it is to use ipchains/iptables to log (but not drop)
    > packets, but this will only tell you a packet got there at this time,
    > not that a specific packet arrived.
            [Hast, Chuck] I need to know the specific packet.

    > Unless you like hacking kernels, pinging is not the answer. I'd setup
    > some sort of UDP client/server with the payload being some encoded time
    > so you know when the packet is sent. You could even stamp the replies
    > with the remote ends clock.
            [Hast, Chuck] I guess this will have to be the way, it is sort of
    the way it
            is being done right now there is just a lot of latency (it is being
    done on
            WinNT) and ping reflects more faithfully the real latency.

    > Getting the clocks right is critical with that sort of thing for obvious
    > reasons.
            [Hast, Chuck] I synch with GPS

    > I'd also look at NTP. A side-effect of what it does is it works out the
    > delay between hosts. It does lots of funky stuff to do it.
    >
    > Of course you can always cheat and use RTT/2 but that assumes symmetric
    > delays.
            [Hast, Chuck] Over RF, symmetric they ain't.... B-[

    > - Craig
    >
    > --
    > Craig Small VK2XLZ GnuPG:1C1B D893 1418 2AF4 45EE 95CB C76C E5AC 12CA
    > DFA5
    > Eye-Net Consulting http://www.eye-net.com.au/
    > <nvnnejj@wplus.net>
    > MIEEE <cuvhm@unimc.it> Debian developer
    > <roijsg.pnqpgo@cas.lt>
    > -
    > To unsubscribe from this list: send the line "unsubscribe linux-hams" in
    > the body of a message to zzcral@vaestoliitto.fi
    >
    >
    *****************************************************************
    This e-mail and any files transmitted with it are confidential and are
    intended solely for the use of the individual or entity to whom it is
    addressed. If you have received this transmission in error, please notify
    the sender immediately and destroy any hard copies you may have printed and
    remove all copies of the e-mail from your hard drive. Opinions, conclusions
    and other information in this message that do not relate to the official
    business of Utility Partners, Inc shall be understood as neither given nor
    endorsed by it.

    Visit us on the web at http://www.utilitypartners.com
    *****************************************************************

    -
    To unsubscribe from this list: send the line "unsubscribe linux-hams" in
    the body of a message to nrnzcg.ochxbj@ntl.com



    This archive was generated by hypermail 2b30 : Wed May 23 2001 - 14:31:56 EEST