Article Summary: This article provides information on how to test available network bandwidth.
How to test available network bandwidth
1. Download the iperf utility. A copy can be found here.
2. On the server that will be receiving data, open a command window and run the following command: "iperf.exe –s –w 2m".
3. On the server that will be sending data, open a command window and run the following command: "iperf –c x.x.x.x –w 2m –t 30s –i 1s". Replace the x.x.x.x with the IP address of the server from step 2.
4. Review the data returned on the server from step 3
Iperf is a commonly used network testing tool that can create TCP and UDP data streams and measure the throughput of a network that is carrying them.
Iperf allows the user to set various parameters that can be used for testing a network, or alternatively for optimizing or tuning a network. Iperf has a client and server functionality, and can measure the throughput between the two ends, either unidirectionally or bi-directionally. It is open source software and runs on various platforms including Linux, Unix and Windows.
The example commands above run a unidirectional test with a buffer size of two megabytes. The test runs for 30 seconds and displays results every second. For a more advanced test see the full syntax below.
[kmKM] format to report: Kbits, Mbits, KBytes, MBytes
print a help synopsis
-i, --interval n
pause n seconds between periodic bandwidth reports
-l, --len n[KM]
set length read/write buffer to n (default 8 KB)
print TCP maximum segment size (MTU - TCP/IP header)
-o, --output <filename>
output the report or error message to this specified file
-p, --port n
set server port to listen on/connect to to n (default 5001)
use UDP rather than TCP
-w, --window n[KM]
TCP window size (socket buffer size)
-B, --bind <host>
bind to <host>, an interface or multicast address
for use with older versions does not sent extra msgs
-M, --mss n
set TCP maximum segment size (MTU - 40 bytes)
set TCP no delay, disabling Nagle's Algorithm
print version information and quit
Set the domain to IPv6
[CDMSV] exclude C(connection) D(data) M(multicast) S(settings)
-y, --reportstyle C|c
if set to C or c report results as CSV (comma separated values)
Server specific options:
run in server mode
run in single threaded UDP mode
run the server as a daemon
Client specific options:
-b, --bandwidth n[KM]
set target bandwidth to n bits/sec (default 1 Mbit/sec). This
setting requires UDP (-u).
-c, --client <host>
run in client mode, connecting to <host>
Do a bidirectional test simultaneously
-n, --num n[KM]
number of bytes to transmit (instead of -t)
Do a bidirectional test individually
-t, --time n
time in seconds to transmit for (default 10 secs)
-F, --fileinput <name>
input the data to be transmitted from a file
input the data to be transmitted from stdin
-L, --listenport n
port to recieve bidirectional tests back on
-P, --parallel n
number of parallel client threads to run
-T, --ttl n
time-to-live, for multicast (default 1)
-Z, --linux-congestion <algo>
set TCP congestion control algorithm (Linux only)
Sources: Wikipedia and Manpagez
Article ID: SLN156921
Last Date Modified: 09/25/2014 01:36 PM