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