Difference between revisions of "Faraday Phone Pouch"
From Gender and Tech Resources
| Line 1: | Line 1: | ||
| − | == | + | == The electromagnetic spectrum == |
| + | The electromagnetic spectrum or electric radio spectrum is not something material, but the space that is in the air that goes from the ground to the highest part of the sky. In this space, bands frequencies through which airplanes, wi-fi, bluetooth, walkie talkies, radios, telephones communicate are organized. The fact that our phones can be 2G, 3G, 4G means that they are using different bands of the electromagnetic space, through which the information circulates. | ||
| − | + | For more information about the electromagnetic space: | |
| − | + | https://imagine.gsfc.nasa.gov/science/toolbox/emspectrum1.html | |
| − | + | https://en.wikipedia.org/wiki/Electromagnetic_spectrum | |
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
== Jaula de Faraday == | == Jaula de Faraday == | ||
| Line 13: | Line 10: | ||
[[File:Jauladefaraday.jpg|centre]] | [[File:Jauladefaraday.jpg|centre]] | ||
| − | + | It is known as a cage or box of Faraday the effect by which the electromagnetic field inside a conductor in equilibrium is null, nullifying the effect of the external fields. This is because, when the conductor is subjected to an external electromagnetic field, it is polarized, so that it is positively charged in the direction of the electromagnetic field, and negatively charged in the opposite direction. Since the conductor has been polarized, it generates an electric field equal in magnitude but opposite in the direction of the electromagnetic field, then the sum of both fields inside the conductor will be equal to 0. | |
| − | + | ||
| − | + | ||
| − | + | It is evident in many everyday situations, for example, the malfunction of mobile phones inside elevators or buildings with steel grid structure. One way to check this is with a radio tuned to a Middle Wave station. When it is surrounded with a newspaper, the sound is heard correctly, but if we replace the paper with aluminum foil, the radio will cease to emit sounds: aluminum is an electric conductor and causes Faraday's cage effect. | |
| − | + | This phenomenon, discovered by Michael Faraday in 1836, has an important application in airplanes or in the protection of sensitive electronic equipment, such as hard disks or radio and television repeaters located on mountain peaks and exposed to electromagnetic disturbances caused by storms . It also currently serves to block the reading of RFID (Radio Frequency Identifiers) chips, which store personal information that can be intercepted by anyone with a radio-frequency scanner. These chips are found in objects such as passports, credit cards and some driver's licenses. | |
| − | + | The Faraday box allows to block the communication of a device with the outside. In the case of mobile phones, they emit signals constantly, even when they are switched off. GPS, which allows us to locate where we are, no matter if it is off or on, also the phone will be locateable by towers that triangulate the signals. The fact that your phone has no signal (when you can not call), does not imply that you are not locateable, or that you have stopped sending signals. | |
| + | Some household appliances work as Faraday boxes, for example the freezer in the refrigerator, as having a thick layer of metal can have the same effect, if we introduce the cell phone inside, we prevent signals from being emitted. | ||
| − | + | About Faraday cage: | |
| − | https:// | + | https://en.wikipedia.org/wiki/Faraday_cage |
| − | + | Experiment of creating a Farady cage: | |
https://backyardbrains.com/experiments/faraday | https://backyardbrains.com/experiments/faraday | ||
| − | == | + | == How they can intercept the information on your phone == |
Una forma de interceptar la información de tu teléfono es a través de un IMSI-catcher, un dispositivo que se puede instalar en cualquier parte (un automóvil, una casa cercana, etc.), y que simula ser la antena de un operador de telefonía móvil. Cuando está instalado, los teléfonos celulares de este operador se conectarán automáticamente con esta antena falsa. Así, este dispositivo localiza e identifica los teléfonos encendidos que estén en el sector, aunque no se estén comunicando, se registran y envían informaciones que lo identifican (como número de teléfono y número de aparato). | Una forma de interceptar la información de tu teléfono es a través de un IMSI-catcher, un dispositivo que se puede instalar en cualquier parte (un automóvil, una casa cercana, etc.), y que simula ser la antena de un operador de telefonía móvil. Cuando está instalado, los teléfonos celulares de este operador se conectarán automáticamente con esta antena falsa. Así, este dispositivo localiza e identifica los teléfonos encendidos que estén en el sector, aunque no se estén comunicando, se registran y envían informaciones que lo identifican (como número de teléfono y número de aparato). | ||
Revision as of 17:37, 1 February 2017
Contents
The electromagnetic spectrum
The electromagnetic spectrum or electric radio spectrum is not something material, but the space that is in the air that goes from the ground to the highest part of the sky. In this space, bands frequencies through which airplanes, wi-fi, bluetooth, walkie talkies, radios, telephones communicate are organized. The fact that our phones can be 2G, 3G, 4G means that they are using different bands of the electromagnetic space, through which the information circulates.
For more information about the electromagnetic space: https://imagine.gsfc.nasa.gov/science/toolbox/emspectrum1.html https://en.wikipedia.org/wiki/Electromagnetic_spectrum
Jaula de Faraday
It is known as a cage or box of Faraday the effect by which the electromagnetic field inside a conductor in equilibrium is null, nullifying the effect of the external fields. This is because, when the conductor is subjected to an external electromagnetic field, it is polarized, so that it is positively charged in the direction of the electromagnetic field, and negatively charged in the opposite direction. Since the conductor has been polarized, it generates an electric field equal in magnitude but opposite in the direction of the electromagnetic field, then the sum of both fields inside the conductor will be equal to 0.
It is evident in many everyday situations, for example, the malfunction of mobile phones inside elevators or buildings with steel grid structure. One way to check this is with a radio tuned to a Middle Wave station. When it is surrounded with a newspaper, the sound is heard correctly, but if we replace the paper with aluminum foil, the radio will cease to emit sounds: aluminum is an electric conductor and causes Faraday's cage effect.
This phenomenon, discovered by Michael Faraday in 1836, has an important application in airplanes or in the protection of sensitive electronic equipment, such as hard disks or radio and television repeaters located on mountain peaks and exposed to electromagnetic disturbances caused by storms . It also currently serves to block the reading of RFID (Radio Frequency Identifiers) chips, which store personal information that can be intercepted by anyone with a radio-frequency scanner. These chips are found in objects such as passports, credit cards and some driver's licenses.
The Faraday box allows to block the communication of a device with the outside. In the case of mobile phones, they emit signals constantly, even when they are switched off. GPS, which allows us to locate where we are, no matter if it is off or on, also the phone will be locateable by towers that triangulate the signals. The fact that your phone has no signal (when you can not call), does not imply that you are not locateable, or that you have stopped sending signals.
Some household appliances work as Faraday boxes, for example the freezer in the refrigerator, as having a thick layer of metal can have the same effect, if we introduce the cell phone inside, we prevent signals from being emitted.
About Faraday cage: https://en.wikipedia.org/wiki/Faraday_cage
Experiment of creating a Farady cage: https://backyardbrains.com/experiments/faraday
How they can intercept the information on your phone
Una forma de interceptar la información de tu teléfono es a través de un IMSI-catcher, un dispositivo que se puede instalar en cualquier parte (un automóvil, una casa cercana, etc.), y que simula ser la antena de un operador de telefonía móvil. Cuando está instalado, los teléfonos celulares de este operador se conectarán automáticamente con esta antena falsa. Así, este dispositivo localiza e identifica los teléfonos encendidos que estén en el sector, aunque no se estén comunicando, se registran y envían informaciones que lo identifican (como número de teléfono y número de aparato).
El IMSI-catcher también puede retransmitir las comunicaciones hacia afuera de un celular en concreto de tal manera que no pueda percibir su presencia. Así podrá tener acceso directo al contenido de estas comunicaciones emitidas que retransmite y puede servir de dispositivo de escucha en vivo.
Más información sobre el IMSI-catcher: https://gendersec.tacticaltech.org/wiki/index.php/Detectar_torres_falsas_de_celular
https://quematumovil.pimienta.org/los_imsi-catchers.html
https://en.wikipedia.org/wiki/IMSI-catcher
Fabricar una funda de Faraday
Hay varias formas de fabricar una bolsa para nuestros dispositivos móviles o tablets con el objetivo de que no sean rastreables y no emitan señales a través de las que nos puedan identificar o espiar.
Hay que conseguir primero que nada la tela conductora. Esta tela la puedes comprar por internet en sitios como estos:
Lo más importante es que cuando hagas la funda no quede ningún espacio abierto por donde se pueda fugar la señal. Fíjate bien de coser todos los bordes, puedes doblar la tela antes de coserla.
La funda se puede hacer con una máquina de coser o a mano. Puedes diseñar una forma de cerrarla, con un botón, con velcro, o simplemente con una pinza.
Si la tela no es muy gruesa ni potente, puedes usarla doble. También puedes, si deseas incrementar la estética de tu funda, usar otra tela para el recubrimiento exterior. Puedes probar distintos diseños y formas, como indica el dibujo:
Medidas de seguridad complementarias a la funda
Usar en grupo la funda puede ser una técnica bastante sospechosa si, por ejemplo, varios móviles vigilados, situados en una misma zona, se apagan o dejan de conectarse a la red al mismo momento. Si se hace de esta forma hará evidente que estas personas tienen algo que esconder o están en algo raro. En ese sentido la práctica más segura sigue siendo dejar tu teléfono en la casa, o al menos, sacarle la batería o meterlo en la funda antes de salir de tu casa para no revelar el lugar de encuentro.
Mucho cuidado ya que la bolsa de Faraday no anula el micrófono. Si bien el teléfono queda incomunicado con el exterior, podría habérselo instalado alguna herramienta que permita grabar para luego enviar dicha grabación. Asegúrate de mantener el teléfono en un lugar aislado acústicamente. Puedes poner el teléfono con su funda dentro de un frasco de vidrio hermético, en el refrigerador, o en otra habitación.
Links de interés
http://briangreen.net/2010/11/diy-ultralight-faraday-cage-pouch.html
http://www.datenform.de/silvereng.html
http://makezine.com/2010/11/18/phonekerchief-blocks-cell-signals/
http://www.backdoorsurvival.com/how-to-build-a-simple-faraday-cage-for-emp-survival/
Tests a jaulas y fundas de Faraday (foros):
http://www.survivalistboards.com/showthread.php?t=156111 http://www.survivalistboards.com/showthread.php?t=231373 http://www.survivalistboards.com/showthread.php?t=301999