Buying a pre-paid phone card or mobile top up calling credit voucher anonymously
Buying a pre-paid phone card or mobile top up calling credit voucher anonymously
Whistleblowers often need to communicate with potential publishers of their disclosures in private. Cheap pre-paid mobile phones can be valuable for this either for voice calls (ideally using a pre-arranged code or pre-arranged "beeping" signals) or by using SMS text messages to arrange face to face meetings and / or whistleblower document disclosure drops or deliveries.
Such mobile phones are now cheap enough for a journalist or blogger (or Confidential Human Intelligence Source handler) to give them out to their whistleblower contacts and to pay for the top up calling credit from their end, rather than potentially exposing the identity of their source.
N.B. A whistleblower or other confidential journalistic sources should watch out for the periodic SMS text messages which are supposed to warn a mobile phone user that their mobile handset has been registered with a web based online Location Based Services tracking service - replying to such a message indicates consent for the tracking to continue Any use of such Location Based Services should be agreed up front by both parties. By default all new phones and SIM cards are blocked from using these "Adult" services so you have to contact the network e.g. at a high street mobile phone shop, for them to flag that handset as being usable for tracking (or for expensive SMS or internet pornography or sex chatlines etc.)
However, just because pre-paid mobile phones are often referred to by the Police and by lazy journalists as "anonymous" , that does not mean that they are.
The Communications Data generated by mobile phones is of three types - Location, Friendship tree (or suspect list of co-conspirators) of which number called which other number , when and for how long and your Subscriber Details.
Buying an "anonymous" pre-paid mobile phone only protects your anonymity from the central registration of Subscriber Details i.e. name and address.
See the Spy Blog "Bring and Swap" presentation given at recent CryptoParty / CryptoFestival events: (.pdf) & (.pptx)
- Expensive, high end smartphones are as powerful as many computers and some models e.g. Apple iPhone attempt to track your usage and identity, especially if you purchase ring tones or music online. Others, like Google Android based phones make a virtue of their Location tracking capabilities. All of these have their uses, but present dangers to a whistleblower trying to contact a journalist or blogger or other intermediary to set up face to face meetings or to arrange whistleblower document deliveries or drops. These phones can cost hundreds of pounds, so they are not usually viable as disposable "burner" phones, unless you are also involved in drug dealing or have a corporate expense account.
- Buy a basic, cheap pre-paid mobile phone from a supermarket etc.. e.g.
VX1 Party Phone unlocked Credit Card sized basic mobile phoneSamsung GT-E1080i -a very basic voice and SMS only phone with a long battery life, available for just £9 to £15 (depending on the special offers) including a free SIM card from one of seven network operators / billing services available from the larger Tesco supermarkets. - You can buy a new pre-paid Mobile Phone from, for example, Tesco or Sainsburys etc., for as little as between £10 to £20 pounds
- Tempting as it is to buy two or more such cheap phones (for the spare battery and power charger alone), do not do so from a Supermarket. These often have arbitrary, unpublished or poorly advertised "rationing" policies in place, limiting the number of such "bargain" phones which an individual customer can buy at a time. You do not want the supermarket checkout operator to have to "consult" with the floor supervisor and have to argue about how many phones you are allowed to buy, not if you are trying to remain forgotten and anonymous in case of future whistleblower leak investigations. Obviously if you are getting a trusted third party to buy the pre-paid mobile phone for you, this may be less of a risk to consider.
- Do not buy the phone handset using a Credit Card or a make use of a Supermarket Loyalty Card, both of which will link to your name and address details.
- Do not buy mobile phone top up credit from your own bank Automatic Teller Machine or online bank account
- Do not top up over the mobile phone e.g. Vodafone 2345, using your own Credit Card / Debit Card.
- Use cash to buy a top up credit voucher from a shop or supermarket, ideally avoiding CCTV cameras.
- Some mobile phone networks e.g. Orange promote the use of plastic swipe card top up cards, which firstly need to be registered to the SIM card and phone number you are using. Obviously these should normally be avoided, but there may be circumstances where they are useful e.g. if journalist or lawyer or blogger (or Confidential Human Intelligence Source handler) gives a mobile phone to their whistleblower source / confidential contact, they can conveniently top up the phone credit remotely at a supermarket checkout or also via the online website.
- It is common practice in the Third World for people in cities (where there are mobile phone shops) to purchase mobile phone calling credit vouchers and then to SMS text message the 12 digit one time code number to their relatives who live in country villages etc. Therefore you can and should buy top up calling credit vouchers at several different locations, ideally getting someone else to do so on your behalf.
- You could get a friend or relative to buy top up calling credit vouchers for you and then communicate the 12 digit code to back to you, using other communications channels. At a push they could phone you up on a different mobile phone and read the numbers off to you, but secure, encrypted email etc. would be better.
- Do not send the 12 digit calling credit top up voucher numbers either via unencrypted, normal, internet email or by SMS text message. Nominally the Interception of the content of such electronic communications would need a warrant signed by the Home Secretary, and it is unlikely that these would be noticed before a whistleblower leak story was published, but they may well be available to a later Leak Inquiry investigation.
- Do not switch on or Activate the new mobile at home or at work, or when your "normal" mobile phone switched on.The first activation of a mobile phone has its physical location specially logged, and it is easy to see what other phones are active in the surrounding Cells at the same time i.e. your own "normal" mobile phone.
- Destroy the paper copies of any top up calling credit vouchers after you have used them, they are of no use to anyone except a future Leak Inquiry investigator - they give details of time, date location of where they were purchased. The voucher number which can obviously be cross referenced to the SIM card and Phone that they were used to top up. If you are a journalist or police officer etc. claiming the cost of this top up calling credit on expenses, then you only need receipts for the amount of money spent, you should not hand over originals or copies of the actual vouchers themselves.
- Do not Register your pre-paid mobile phone, despite the tempting offers of "free" phone credit.
- Second hand mobile phone handsets can be bought online, but this obviously leaves a Credit Card or PayPal etc. electronic transaction trail, so do not bother.
- Second Hand mobile phone handsets are often available at non-mobile phone network shops or at counters within a larger shop, usually offering Mobile Phone Unlocking, repairs, mobile phone accessories like coloured casings etc. and spare batteries and chargers etc. which the mainstream Mobile Phone shops no longer bother with. They often cater to local immigrant communities who have foreign registered mobile phones which they want to use ion UK networks. Phone Unlocking from one network to another is not illegal, but re-programming the IMEI is (up to 5 years in prison even for advertising such a service), because of the legal fiction that stolen mobile phones could only ever be unblocked in the UK, rather than overseas as they have always been.
The disadvantage with this sort of purchase is that they are often more expensive than a new low end Supermarket phone and they could have been previously used by drug dealers or illegal immigrants etc. who are already being tracked electronically by the authorities. These shops do not usually have extensive CCTV camera video recordings like supermarkets, but they are likely to be regularly questioned by the Police etc. so the shop assistant / proprietor may quickly "cooperate" with any Leak Inquiry investigation, if you are in any way memorable.
Pre-paid cards for public phone boxes
Exactly the same precautions are need for other pre-paid phone cards, such as those which are used in public phone boxes, to replace cash or coins.
Obviously do not make a call using your own Credit Card (which can be done in some public phone boxes, or, on some airliner flights).
All of these have unique serial numbers which can be used to link together a pattern of phone calls, so if you do choose to use one for contacting a journalist or politician or whistleblowing supervisory authorities or for any such people to contact their whistleblower contacts, then no other phone numbers such be used, even if there is still credit left on the card or the voucher. i.e. do not call your family or friends or work colleagues using the same pre-paid card card (or mobile phone) as which you use for whistleblower communications.