


BING(8)            UNIX System Manager's Manual           BING(8)


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 pack-
       etsize] 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 pack-
            ets.

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

       -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



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BING(8)            UNIX System Manager's Manual           BING(8)


            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 packet-
            size.

       -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.



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BING(8)            UNIX System Manager's Manual           BING(8)


       -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  mini-
       mum/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,  mea-
       surement 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>























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