A transparency campaign from

Run your own probe

We need people to help by running their own probes

This is quite easy.

You can help ORG’s blocked project by running a probe yourself. It can run a clean line, or a filtered line, we don't mind. Or you can have filters enabled for a period of time, and we will detect that they are running.

Clean line probes help us look for domain suspensions, Error 451 responses and court order blocks. Filtered lines help us document mistakes and overblocking by ISP filters. 

In the UK, we are very interested in probes on:

  • TalkTalk, to measure the frequency of filters switching themselves on and off, as well as documenting the filters
  • Virgin, BT, Sky, KCom to test for court order blocks and domain suspensions, and / or filtered websites
  • Filtered networks provided by the public sector in schools, hospitals and libraries

We are looking to place probes across Europe as part of our project with EDRi members to document copyright court orders and other Internet censorship.

How to get a probe

You can do this in one of the following ways:

  1. Order a preconfigured probe from ORG. Please donate towards the cost of a probe, each one costs £45.
  2. Buy your own RPI 3 model b, power supply and ethernet cable, and download a disk image (we supply unique images on request).
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Setting a probe up

This is very easy.

  1. Plug in the probe
  2. Ensure the ethernet cable is connected and DHCP is working to assign an IP address.
  3. The probe registers with our middleware automatically. Ask us to confirm it is working.

Maintaining the probe

We maintain the software by automatically updating the probe. You don't need to take action, but we may occassionally ask you to reboot it if something goes wrong.

Please keep the probe powered up if you can.

Bandwidth consumption

We are conscious that these lines are being placed on normal consumer lines, and you don’t want all of your bandwidth used up by our probe. For this reason, we schedule requests to be made more frequently at night and at the weekend. 

Data usage is fairly light. The probe requests normal HTML pages and does not attempt to load dependent images, CSS libraries, fonts and so on. Data usage would normally be about 500mb-1gb per month.

If this doesn’t suit your usage patterns, we can change the scheduling per probe. You can also disconnect or switch the probe off if it is causing inconvenience.

Security measures

While we do our best to ensure the probe is safe to use, you may like to ensure that it cannot be abused, and is what we say it is. We recommend:

  1. That you place the probe on a sandboxed part of your network, so it cannot see or communicate with other local machines.
  2. That you request a log in from us, so you can check what is on the machine itself.

Warning: things you need to know

You should understand that domains or URLs may be requested that contain illegal material, if users add these through the blocked.org.uk checking tool. As nothing is stored or viewed by you, there is little chance that anything illegal is taking place. However, there is a slight possibility that the police might think something odd is taking place.

It is also possible that an ISP may object to our work and view it as a breach of terms and conditions. 

Neither of these situations has arisen yet.

Letters from ISPs such as Virgin about Viruses and malware

As we run very wide tests on millions of domains, a few of these will turn out to be owned by malicious actors for use in "command and control" botnets. These domains are blocked by many ISPs. When our probes check a domain which is listed as malicious by Virgin, TalkTalk or BT, they may send a letter to you explaining that you are likely to be infected by malware, as something on your network sent a request to a malicious domain.

This does not mean that you should simply ignore such letters, especially if you have reason to believe that some equipment on your network may be infected, but please be aware that this may take place.


Supported by

Andrews and Arnold Ltd  :Bytemark Hosting  Top10VPN

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