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WiscNet hosted Speedtest.net

For a quick and easy reading, you may use to use an HTML based browser test:


WiscNet hosted IPERF

Iperf is a commonly used network testing tool to help measure network throughput. Since it is an open source tool, there are clients for Windows, Mac, Linux, Bsd, etc. It will generally give you more detailed results than a browser based speedtest.

Iperf operates where one end is the client, the other is the server. WiscNet runs an IPERF version 2 server in Eau Claire, WI. TCP is port 5001, UDP is port 5002. The server is restricted to WiscNet IP addresses. 

Examples

iperf.wiscnet.net runs a TCP Iperf server on the default port (5001)

    iperf -c iperf.wiscnet.net -i2

 

iperf.wiscnet.net runs a UDP Iperf server on port 5002. this test uses UDP, sends 20Mb/s, reports every 2 seconds, runs for 30 seconds

    iperf -c iperf.wiscnet.net -u -b20M -p 5002 -i2 -t30

 

iperf.ipv6.wiscnet.net runs a v6 TCP Iperf server on port 5003

    iperf -V -c iperf.ipv6.wiscnet.net -p 5003 -i2

 

iperf.ipv6.wiscnet.net runs a v6 UDP Iperf server on port 5004

    iperf -V -c iperf.ipv6.wiscnet.net -p 5004 -i2 -u


TCP vs UDP testing

Iperf uses TCP by default. TCP has built in congestion avoidance. If TCP detects any packet loss, it assumes that the link capacity has been reached, and it slows down. This works very well, unless there is packet loss caused by something other than congestion. If there is packet loss due to errors, TCP will back off even if there is plenty of capacity. iperf allows TCP to send as fast as it can, which generally works to fill a clean, low latency link with packets. If a path is not clean/error free or has high latency, TCP will have a difficult time filling it. For testing higher capacity links and for links with higher latency, you will want to adjust the window size (-w option). See the KB article on TCP performance for more background.

By using the -u option, you have told iperf to use UDP packets, rather than TCP. UDP has no built in congestion avoidance, and iperf doesn't implement it either. When doing a UDP test, iperf requires that the bandwidth of the test be specified. If it isn't, it defaults to 1Mb/s. You can use the -b option to specify bandwidth to test. iperf will then send packets at the request rate for the requested period of time. The other end measures how many packets are received vs how many were sent and reports its results.

Bidirectional tests

When you use the -d or -r options for bidirectional testing, you may need to pick a port other than the default [5001] as the server is listening on port 5001. In the below examples, I random ports above 1024 were chosen.

We found that using the same port (with the -L) option in rapid succession doesn't seem to work.

The simultaneous test results may be difficult to read. It looks like only TCP is working. UDP doesn't appear to be working even after upgrading to iperf-2.0.4 [there were supposed to be some bug fixes]. It appears to be a problem in the official distribution according to recent ubuntu forums.

 

If you do not pick a port it will fail:

C:\>iperf -c iperf.wiscnet.net -i1 -d
bind failed: Permission denied


Simultaneous, local port (-L) 20000:

C:\>iperf -c iperf.wiscnet.net -i1 -d -L 20000
------------------------------------------------------------
Server listening on TCP port 20000
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
------------------------------------------------------------
Client connecting to iperf.wiscnet.net, TCP port 5001
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
[1848] local 146.151.208.16 port 2242 connected with iperf.wiscnet.net port 5001
[1820] local 146.151.208.16 port 20000 connected with iperf.wiscnet.net port 20000

[ ID] Interval       Transfer     Bandwidth
[1848]  0.0- 1.0 sec  1.03 MBytes  8.65 Mbits/sec
[1820]  0.0- 1.0 sec  1.05 MBytes  8.83 Mbits/sec
[1848]  1.0- 2.0 sec  1.09 MBytes  9.11 Mbits/sec
[1820]  1.0- 2.0 sec   911 KBytes  7.46 Mbits/sec
[1848]  2.0- 3.0 sec   976 KBytes  8.00 Mbits/sec
[1820]  2.0- 3.0 sec  1.05 MBytes  8.79 Mbits/sec
[1820]  3.0- 4.0 sec  1.33 MBytes  11.1 Mbits/sec
[1848]  3.0- 4.0 sec   672 KBytes  5.51 Mbits/sec
[1848]  4.0- 5.0 sec   712 KBytes  5.83 Mbits/sec
[1820]  4.0- 5.0 sec  1.38 MBytes  11.5 Mbits/sec
[1848]  5.0- 6.0 sec   624 KBytes  5.11 Mbits/sec
[1820]  5.0- 6.0 sec  1.42 MBytes  11.9 Mbits/sec
[1848]  6.0- 7.0 sec   584 KBytes  4.78 Mbits/sec
[1820]  6.0- 7.0 sec  1.53 MBytes  12.9 Mbits/sec
[1848]  7.0- 8.0 sec   832 KBytes  6.82 Mbits/sec
[1820]  7.0- 8.0 sec  1.26 MBytes  10.5 Mbits/sec
[1848]  8.0- 9.0 sec   616 KBytes  5.05 Mbits/sec
[1820]  8.0- 9.0 sec  1.49 MBytes  12.5 Mbits/sec
[1848]  9.0-10.0 sec   584 KBytes  4.78 Mbits/sec
[1820]  9.0-10.0 sec  1.51 MBytes  12.7 Mbits/sec
[ ID] Interval       Transfer     Bandwidth
[1848]  0.0-10.0 sec  7.59 MBytes  6.34 Mbits/sec
[1820]  0.0-10.1 sec  13.1 MBytes  10.9 Mbits/sec



Back to back test (-r). The server to client test comes AFTER the client to server test:

C:\Documents and Settings\m7h>iperf -c iperf.wiscnet.net -i1 -r -L 60000
------------------------------------------------------------
Server listening on TCP port 60000
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
------------------------------------------------------------
Client connecting to iperf.wiscnet.net, TCP port 5001
TCP window size: 8.00 KByte (default)
------------------------------------------------------------
[1848] local 146.151.208.16 port 2365 connected with iperf.wiscnet.net port 5001
[ ID] Interval       Transfer     Bandwidth
[1848]  0.0- 1.0 sec  2.02 MBytes  17.0 Mbits/sec
[1848]  1.0- 2.0 sec  1.91 MBytes  16.1 Mbits/sec
[1848]  2.0- 3.0 sec  1.92 MBytes  16.1 Mbits/sec
[1848]  3.0- 4.0 sec  1.92 MBytes  16.1 Mbits/sec
[1848]  4.0- 5.0 sec  1.92 MBytes  16.1 Mbits/sec
[1848]  5.0- 6.0 sec  1.95 MBytes  16.3 Mbits/sec
[1848]  6.0- 7.0 sec  1.98 MBytes  16.6 Mbits/sec
[1848]  7.0- 8.0 sec  1.95 MBytes  16.4 Mbits/sec
[1848]  8.0- 9.0 sec  1.89 MBytes  15.9 Mbits/sec
[1848]  9.0-10.0 sec  2.04 MBytes  17.1 Mbits/sec
[1848]  0.0-10.0 sec  19.5 MBytes  16.4 Mbits/sec
[1824] local 146.151.208.16 port 60000 connected with iperf.wiscnet.net port 60000

[ ID] Interval       Transfer     Bandwidth
[1824]  0.0- 1.0 sec  2.22 MBytes  18.6 Mbits/sec
[1824]  1.0- 2.0 sec  2.18 MBytes  18.3 Mbits/sec
[1824]  2.0- 3.0 sec  2.17 MBytes  18.2 Mbits/sec
[1824]  3.0- 4.0 sec  2.22 MBytes  18.6 Mbits/sec
[1824]  4.0- 5.0 sec  2.01 MBytes  16.9 Mbits/sec
[1824]  5.0- 6.0 sec  2.16 MBytes  18.1 Mbits/sec
[1824]  6.0- 7.0 sec  2.09 MBytes  17.5 Mbits/sec
[1824]  7.0- 8.0 sec  2.07 MBytes  17.4 Mbits/sec
[1824]  8.0- 9.0 sec  2.16 MBytes  18.1 Mbits/sec
[1824]  9.0-10.0 sec  2.13 MBytes  17.9 Mbits/sec
[1824]  0.0-10.1 sec  21.6 MBytes  17.9 Mbits/sec



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