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Test connectivity

There are several ways to confirm basic connectivity between hosts, whether the hosts are within a TAN or not.


Ping is a well-known and long-established method of confirming that a host is able to communicate with another host.


Many firewalls are configured to drop ICMP, or ping, messages, so ping is not a reliable indicator of service.

On the source host, open a command prompt. Enter:

ping <target>

Replace <target> with the IP address or hostname of the target host.


On Windows, the default behaviour is to send 4 pings and stop. On Linux and similar OSs, the default is to send until interrupted by the user. A limited number of pings can be sent by adding -c <n> to the command, where <n> is the number of pings to send.



A good alternative to ping is using iperf3 to generate dummy traffic between two hosts. This is also less likely to be affected by firewall rules dropping certain types of traffic.

Download iperf3 from their website and install on at least two different hosts.

On one host, open a command prompt and run iperf3 as a server:

iperf3 -s

iperf3 as a server

The output includes a port number (5201 in the screenshot). The client needs this number to connect.

On the second, client, host, open a command prompt and run iperf3 as a client:

iperf3 -c <target> -p <port>

Replace <target> with the IP address of the server, and <port> with the port number from the server.

iperf3 client

iperf3 server receiving data

The user documentation for iperf3 describes how the generated traffic profile may be modified.


There are public iperf3 servers on the Internet, which may also be useful for testing connectivity.

Streaming video

A richer connectivity test or demonstration can be achieved by streaming video.

Download and install VLC on at least two hosts.

A suitable source or video file to be streamed is required.


One host will act as the server. On this host:

  1. Start VLC.
  2. Select Media, then Stream (or press CTRL + S)
  3. On the File tab, click +Add...
  4. Click the Stream button
  5. Click Next
  6. Select RTP/MPEG Transport Stream and click Add
  7. Enter the address of the host that will view the stream
  8. Set the base port to 5555
  9. Click Next
  10. Uncheck Activate Transcoding
  11. Click Next, then Stream to start the stream
Selecting a file to stream
Selecting a file to stream
Stream output
Stream output



Add a firewall exception for incoming UDP packets on port 5555.

On the client host:

  1. Start VLC
  2. Select Media, then Open Network Stream... (or press CTRL + N)
  3. Enter the network URL rtp://@:5555

Playback should start when setup has been completed on both computers.