NAME

       bing  -  compute point to point throughput using two sizes of ICMP ECHO_REQUEST packets to
       pairs of remote hosts.

SYNOPSIS

       bing [dDnrRPvVwz] [-c count] [-e samples] [-f samplefile] [-i wait] [-p pattern] [-s small
       packetsize] [-S big packetsize] host1 host2 [...]

DESCRIPTION

       Bing  determines  bandwidth  on a point-to-point link by sending ICMP ECHO_REQUEST packets
       and measuring their roundtrip times for different packet sizes on each end of the link.

       host1 is supposed to be the nearest end of the link, while host2 is the other end.

       The options are as follows:

       -c count
            Stop after count resets of the stats. Useful only in conjunction with the -e  option.
            Defaults to 1.

       -d   Set the SO_DEBUG option on the socket being used.

       -D   Display the measured throughput at every received packet. By default, it is displayed
            only when the computed value changes, which itself  changes  only  when  the  minimum
            roundtrip time for one of the packet sizes changes.

       -e samples
            Reset stats after sending samples ECHO_REQUEST packets.

       -f samplefile
            Saves the bandwidth measurements to the file samplefile.

       -i wait
            Wait  wait  seconds  for  each  ECHO_REPLY  packet.  The  default is to wait for four
            seconds.

       -n   Numeric output only. No attempt will be  made  to  lookup  symbolic  names  for  host
            addresses.

       -P   Be pedantic regarding round-trip times.

            Normally,  bing  assumes  that the roundtrip time for a small packet should always be
            smaller than the roundtrip time for a big packet to the same host, that for  a  given
            size  the  roundtrip  time for host1 should always be smaller than the roundtrip time
            for host2, and that the increase in the roundtrip time between host1 and host2 should
            always be bigger for big packets than for small packets.

            Bing takes advantage of this to better determine the minimum roundtrip times.

            Option  -P  disables  this  behaviour,  in  the unlikely event it could be of any use
            someday. Even IP/X25 links are not weird enough to require this, though.

       -p pattern
            You may specify up to 16 ``pad'' bytes to fill out the  packet  you  send.   This  is
            useful  for  diagnosing data-dependent problems in a network.  For example, ``-p ff''
            will cause the sent packet to be filled with all ones.

       -R   Record route. Includes  the  RECORD_ROUTE  option  in  the  ECHO_REQUEST  packet  and
            displays  the route buffer on returned packets. Note that the IP header is only large
            enough for nine such routes. Many hosts ignore or discard this option.

       -r   Bypass the normal routing tables and send directly to a host on an attached  network.
            If  the host is not on a directly-attached network, an error is returned. This option
            can be used to ping a local host through an interface that has no  route  through  it
            (e.g., after the interface was dropped by routed(8)).

       -s small packetsize
            Specifies  the  number of data bytes to be sent in the small packets. The default and
            minimum value is 44.

       -S big packetsize
            Specifies the number of data bytes to be sent in the big packets. The default is 108.
            The  size  should  be chosen so that big packet roundtrip times are long enough to be
            accurately measured (depending on clock resolution and number of hops).

       -u size increment
            Specifies that bing should start sending packets of the size of small packetsize  and
            then increase the size by size increment until it reaches big packetsize.

       -v   Verbose output. ICMP packets other than ECHO_RESPONSE that are received are listed.

       -V   Very verbose output. The roundtrip time of each received echo is displayed.

       -w   Display  possible  warnings about roundtrip times all the time.  By default, warnings
            are printed only at the end.

       -z   Fill packets with uncompressible (pseudo-random) data.

       Round-trip times and packet  loss  statistics  are  computed.  If  duplicate  packets  are
       received,  they  are  not included in the packet loss calculation, although the round trip
       time of these packets is used in calculating the minimum/average/maximum  round-trip  time
       numbers. When the specified number of loops have been made or if the program is terminated
       with a SIGINT, a brief summary is displayed.

       This program is intended for use in network testing, measurement and  management.  Because
       of  the  load  it  can  impose  on  the  network,  it  is unwise to use bing during normal
       operations or from automated scripts.

BUGS

       Many Hosts and Gateways ignore the RECORD_ROUTE option.

       The maximum IP header length is too small for options like RECORD_ROUTE to  be  completely
       useful. There's not much that that can be done about this, however.

       Some  of the final stats (average throughputs) almost never give a even marginally correct
       result.

SEE ALSO

       netstat(1), ifconfig(8), ping(8), routed(8), traceroute(8)

AUTHOR

       Pierre Beyssac <pb@fasterix.freenix.fr>

       Port to Windows: Francois Gouget <fgouget@mygale.org>

                                          April 3, 1995                                   BING(8)