Discussing RFID

edited February 2015 in RFID/NFC
Since there hasn't exactly been a hell of a lot of activity on this forum as of late, I thought I'd see if I can reinvigorate anything.  Much of the inactivity seems to be due to some projects stalling, so, in the meantime, how about something a little more straightforward?

We all probably know what a RFID chip is, and why someone would want to implant one.  This hack was the first procedure done by many grinders, and is rather straightforward.  With this in mind, it seems somewhat surprising that it hasn't gotten an awful lot of attention here.  One of the reasons is probably that it's not necessarily the most useful thing to implant, especially if security is what you're after.

Some examples of RFID implanting can be found in Lepht Anonym's blog, since RFID was its first hack, the Evolution by Proxy blog, which talks about @SixEcho and @Hughligen's procedure, and, of course, Amal Graafstra's book, RFID Toys.  However, the point of this thread is to stimulate discussion on the topic; most importantly, some novel uses for RFID and how to go about doing them.  Possibly, this discussion can give people ideas, either about RFID, or about a similar concept in other projects, and if it gives one person such an idea, I think the discussion will have been worth it.

I'll start with an idea to mildly increase the security of RFID:  you know those aluminium-lined sleeves that people keep their ID cards (with similar chips) in, to prevent it from broadcasting when they don't need it to?  I was thinking of making a small glove-like object, lined with the same material, which you could take off when you need to use the chip.  Of course, the question now becomes "who would even be willing to wear that thing all the time?"

Another idea, which was first mentioned on the Evolution by Proxy blog, was a group-buy for RFID readers.  There's quite a few suppliers to choose from, so if anyone's interested in that, we might want to set one of those up.



  • Ugh, do I have to go on io9 again...?

    Actually, this article's pretty cool, and the discussion isn't yet quite as full of douchebags as it usually is.

  • Hey all, completely new here, and since I am looking for practical ways to start delving into some simpler biohacks I thought I might voice a fear here and bump the thread. Has there been any discussion as to unwanted side effects of having rfids re: others being able to identify you with a scanner? Of course, the offender would need to grab your chip's number first; therefore also, is this possible with a simple scanner? Imagine when the grinding movement gets big someday, and someone gets caught committing a crime. The larger implications of the general public thinking it is justifiable for the, say, police to carry scanners because grinders are all "just metal faced weirdos" its a bit frightening to say the least.

    Sorry if this question its out of line. American here. Doesn't seem an unrealistic fear anymore.
  • you can be scanned, but that's about the same as getting photographed. reading distance of those glas capsule tags usualy ranges between a few millimeters. and bout 20 or 30cm if you have a really good reader.

    rounded up: RFID implants do carry a certain risk of beeing identified automatically, but compared to other technologies the use of it is sorta limited.
    so for now, it is nothing but a toy.
    compare to japan's high-end face-recognition project that can scan 40mio faces per second from public surveillance cameras.
  • Alright, thanks for the reassurance. That in mind, I had an idea for a device setup that I decided might be possible to do with RFID. Without having to read a large manifesto (google -> howstuffworks article is 10 pages long and I have all of fifteen minutes of computer time at this precise moment), I was wondering if it is possible to regulate "when" the RFID implant would send out its signal, and what sort of input device is needed - say, if you could use one of the ND magnets in your finger to trigger its signal if that was possible. Just as an example.

    And the point of that is, say you put about five in your arm, and keep a smartphone with an RFID reader in your pocket. Can you create a wireless keypad on your person?

    Coupled with coming up with some kind of audio device (or just a plain-ol earbud), my idea with this is to be able to access an audiobank like one would google something visually on a phone, but so much quicker and requiring less direct attention - and without having to use voice.
  • @Sarcose:  It's not like that; RFID chips aren't just sending out a signal, waiting to be picked up at a reader's request; they work passively.  What happens is the reader creates a magnetic field, which induces a current in the RFID chip, making it send out the signal.  So, the chips are already designed to only send out a signal in the presence of a magnetic field.
  • edited April 2012
    I actually read that today a while after I made my post; that is specifically the kind of RFID that have an iteration designed for implanting, though, right? There are apparently RFID tags, used for inventorying and such, which are battery powered and broadcast their signals. But I am assuming the issue of implanting these is quite a bit more complex and not exactly something everyone is discussing at great length right now? 

    I'll have to give this thing a read: http://alumni.media.mit.edu/~deva/papers/senseid.pdf , because I'm still interested in this concept and it seems to be the best candidate for my purposes - rather than just using it as a binary controller (read, not-read), I'd like a way of signalling a device with multiple and combinable inputs...

    Edit: Unless... since I am assuming the passive RFID implant would not have the range, the reader would have to be very close, like possibly annoyingly taped to the shoulder, but if they need that magnetic field already, would the ND magnets in the finger have enough of one or would you need to go bigger, and would generating the power necessary to signal without using the reader still send a signal the reader can catch? If both of these are doable one could still piece together a control mechanism that responds to the different chips.
  • Well, you could do the battery-powered one, but then you have all sorts of issues.  Like, the battery running out, and stuff, though you could probably charge it by induction.

    I don't know whether the Nd implants would work for that, but either way, you also have to have something that can read the signal.

    Now, there is actually a tutorial on programming stuff in Arduino, and one of the episodes is about building and programming a RFID reader.  Now, that's interesting; I've long thought that I should try building that myself.

  • if anyone is interested, i still have c-code that makes an atmega read the output from atmels rfid base station ic.
  • edited April 2012

    Thanks for the link and the offer. I'll take a look at them sometime and start to piece together what I want to do with this. I need to actually figure out what I'm doing first and that is going to take some googling and research and discussion with my engineering-major friend.

    Briefly though, I realized last night I was going about this wrong. It was quite a headslapping moment in fact. The Nd implants wouldn't work for the same reason an RFID reader isn't just going to normally be self-powered, because the power source isn't strong enough. That got me thinking, the activation mechanism could be a reader itself. If we could get an implantable reader that signals out to another wireless device it would serve my purposes - in fact it would be ideal I think; by making the RFID chips into trigger sights rather than signalers themselves and centralizing the signaling and main power supply of the system, thus cutting down on necessary complexity. The task is probably quite beyond me now, but for the time being I am making that my baby and a reason to get me learning.

    However, to spark further discussion again, I'd like to ask what kind of experiences others have had with RFID chips migrating. I had this "genius" plan of putting multiple in one arm and using it kind of like a keypad given the right scenario but then I realized that even if I marked where they were they would probably move around and jumble up if they were just right next to each other. If I put maybe two in my arm - one up near the wrist, one closer to the elbow, I'd have easier sites to manage. One in the back of my hand then, one up on my shoulder, and I'd have a pretty good system for keeping them separated, but it would look fairly ridiculous, me rubbing my hand over my arm and tapping it at different spots. The cool factor goes down quite a lot if I don't have the sites in one spot - also the subtlety.

    So what have others experienced in terms of chips migrating? Has anyone had any luck keeping them from doing so, or, since it seems the only use for RFID right now is magic wand in your hand to open things, has anyone even cared about those minor migrations?

    edit and addendum: I also want to mention that the reason I'm looking at RFID for this is because I feel its simplicity has a lot of potential for input/output scenarios, given the right amount of creativity and duck tape. And also, the RFID implants are a known quantity that are understood to work as advertised, as opposed to designing, from scratch, some kind of implantable "button".
  • edited April 2012
    migration is hardly a problem. stuff pretty much remains where you put it. mine hardly moved a cm, maybe rotated a tiny bit. same thing for a friend of mine.
    there are better ways to communicate with your implant tho.
    reading biopotentials from muscle activity, acceleration, light,...
  • edited April 2012
    What I'm mostly interested in is a direct input controller scenario moreso than anything that would be automatic or difficult for me to have a precise influence over.
  • Also if I may, the ultimate plan is to communicate with a smartphone wirelessly rather than an implant, which is a hurdle I'll come to when I design the RFID reader/relay combo, however you want to describe it. The reason for a smartphone is that until I am say older and wealthily successful, I don't expect to be able to biohack something into my body with quite as much functionality as a smartphone without a data plan - a tiny, powerful, unconnected computer, that is. The smartphone would be for controlling various things such as accessing data in audio format to "look" things up on the fly without having to completely distract myself, performing around the house tech tasks such as interacting with my desktop PC... more things when I come up with them.

    This is, again, a longterm plan. Again, I did think of something say, for instance, tiny bluetooth devices that would relay a signal when pressed, but a number of reasons made me look into RFID, some of those being the sheer simplicity and the "security" of not being able to interact with them without a reader - essentially, only my finger with the reader+relay would be able to "press" them. Since I wouldn't use them for opening/closing except nominally, the big security issues being foreseen wouldn't really resonate with me much. I could just wear an aluminum lined sleeve if that were the case, however.
  • edited April 2012
    Incidentally, say I have a theoretical array of RFID chips implanted into an area and they happen to be too close to each other, such that any reader I put near the intended chip has a chance or tendency to stimulate and pick up a signal from one of the other chips.

    Now, a shitty ASCII diagram:
    || || ||
    o o o o

    Let's cal the o's the rfid chips, and assume that the reader is intended to be placed directly above them to trigger the signal, where the "V" is. But, through some miscalculation - my skin density/salt content/whatever is too thin and does not dampen the signal like I thought, or the reader is too strong, for instance - one of the adjacent chips receives enough of the magnetic field to send out its signal, and suddenly two of the "buttons" are pressed at once. Would bioproofed aluminum "barriers", placed at the locations indicated by " || ", have a decent chance of preventing the signal from crossing over? Assume the "V" is where I intend to need to press the reader to, and the V is outside the skin while the aluminum barriers and the chips are inside the skin. The theory I am going with here is that, while the signal might cross over, being blocked on the direct "diagonal" to the reader would enable me to limit the signal to transmissions directly over the chip -- making another assumption, of course, that the RFID reader is not inherently strong enough to trigger and pick up the signal of a chip without first being really close, as in touching the skin above, the chip, which would be the undesirable scenario I'd be trying to avoid in putting it together.

    This is all hugely theoretical. I don't know if standard designs of readers would put their base signal strength at too much to do this sort of thing, for instance.
  • you can easily tune a "too strong" base station down.
    to give you an idea about reading distance. if you go with the atmel chip for a base station then there are a number of different circuits in the datasheet.
    with the most simple one you can get about 5 ot 10mm reading distance for a glass tag. the most complex one gives you maybe 5 to 15cm if you have it incredibly well tuned.

    aluminum sheets are not a good idea for multiple reasons.

    in general, tags behave pretty much the same in and outside the skin. so you can test your setup quite well on the bench, and then decide if it is worth implanting or not.
  • edited April 2012
    Alright then, I assumed aluminum would be bad, and that's good to know that the skin doesn't change the signal much; I was worried about botching basic testing.

    I would love it if you directed me to any information or materials such as that, and I'd file them away in a folder for use when I get up to the technical level of working with it.

    Right now my goal is to get together a surgical kit for next month when I'm meeting with a friend and we're going to spot each other on our first magnets.

  • OKAY given my recent discussions in IRC I have a bit of a different plan for I/O that doesn't directly involve RFID. However I do have a query that is somewhat relevant:

    since transdermals are still iffy and I don't want anything sticking out just yet, I was wondering if it would be possible to use RFID as an example and "hop" a really weak radio signal through the skin - the signaler would have to be written to on the fly, then send its signal out. In other words, you hit a button and it sends a weak radio signal through the skin of "1000" for example, which wouldn't even do anything unless the reader right on the other side could pick it up. 

    Assuming the external reader didn't trigger it, or perhaps when the "button" is not being pressed, the information on the signaler becomes inert to the reader's software e.g., it doesn't respond to that signal.

    So basically, is there a way to write to RFID with implants? For my purposes the amount of data RFID can send is far more than I need, so if there is something even simpler that would work.
  • that wouldnt precisely be RFID anymore. as you dont identify anything with radio frequencies anymore.

    transmitting a signal via electromagnetic fields is pretty easy. for just a few buttons you have 2 options.

    option 1: having an oscilator circuit where your button-presses change the resonance frequency. by detecting the frequency on the base station you can figure out which buttons are pressed (this is used in stuff as drawing tablets, and works with very few passive parts and uses minimum space)

    option 2: go the rfid-way. have an oscilator circuit  that dampens the signal of the base station. you need more smartness on the implant side. a microcontroller for example. if you power it inductively over the same coils it is still sane  to do.

    in both cases you need to arrange the implanted induction-coil. and the base station coil. expect a reading range with a maximum somewhere between 2 and 3 cm
  • Sourcing the RFID chips themselves seem to be my biggest issue right now, honestly. I've been referred to suppliers in faraway places who may or may not be able to get anything useful to my doorstep. But say I do find and obtain one. Any major problem with self-implanting? Sourcing a professional may end up even trickier than sourcing the device! And I've read and heard that it's a relatively simple operation as far as implants go. Thoughts?
  • if you are looking for tags to implant, i can highly recommend the animal-identification tags. they are proven to be save in millions of living creatures, mass produced, and they come with a convenient to use applicator. Most veterinarian stock them. with a bit of luck you can even find them online.
    i found mine on http://www.vets4petz.nl/back-home-transponder-biotec-p-404.html?language=nl , there might be other resellers near you.

    most of those tags arent HITAG compatible. so most readers wont read them out without modification. building your own base-station solves this problem.

    with an applicator. all you need is someone to help you pulling up your skin a bit , inject the needle, gently push out the tag while pulling out the needle, done. implanting a tag with applicator is easy, there are many vids on youtube showing it. without applicator, it's a mess.

    you could also use an applicator and a regular industrial glasstag. many people did this for compatibiltiy reasons. personally i wouldnt recommend it.
  • edited January 2013
    I know this is an old thread, but I just joined so I figure I'd put my 2 cents up here. I would not go with an animal implant for two reasons; first, it has a parylene coating that is unnecessary and makes removal/replacement very difficult. The second reason is that bio-compatible glass 125KHz EM4102 and 13.56MHz Mifare S50 ISO 14443A tags are readily available, and can be used with highly available, very cheap reader hardware with no modifications.

    That said, I'm going to honor my first post here with a shameless plug. It's been 3 months shy of 8 years since I got my implants, and all that time I've answered people's questions and tried to help others source gear and do their DIY procedures in the safest way possible. All this time, people have asked me if I sold implants or DIY kits and I've always had to point them to various places, with some turning out to be unreliable.

    I believe our bodies are our own, to do with what we want, and that lifehacking/biohacking/grinding is at the forefront of a new kind of technological wetware revolution. Just as science fiction stories are made true by fanboys who became engineers, what we all doing now is having a direct impact on our collective human experience and way of life. The "socially acceptable" of tomorrow is being dragged forward by the boundaries we're all pushing today, and I'm excited to be a part of it.

    For my part, I want to try to provide easier access to safe gear and safe procedural guides. I've decided to start up www.dangerousthings.com, which only has a few items at the moment, but I will be trying to scale up inventory and take requests for new stuff. Please let me know what you think.
  • amal 
    That's pretty cool, thank you for selling these implants, it provides a real service to the community.

    I'm thinking of getting one myself and I am wondering, with regard to the S50 implant, it has 1k of memory, which is quite a lot, how many write cycles do these chips have?

  • What Ammon said - thanks amal, this is the kind of site some of us have been looking for.  Please continue to update your list of body modification businesses, as your time & inclination permits.

  • @AmmonRa - These S50s are rated for over 100,000 writes per block.

    I am working on a pain management kit (PMK) and should soon be able to provide 99% pure Lidocaine HCL crystals (water soluble) and I'm working on a custom concoction of Lidocaine + DMSO. The PMK will likely come with ingredients and "instructions" since there happen to be legal restrictions on selling compounds (I mix it vs you mix it).

    Any other suggestions for products/services are also welcome.
  • Thanks, have ordered mine. I'll document the process for those that are interested.
  • I just got my rfid chip in the mail, so figured I'd post an update. you can see the chip itself in the top centre (the small black thing) and insertion kit in the bottom left, amal also included a printed copy of all the docs available on his dangerousthings site (implant guide and nfc specs/details).
    I haven't really played with it much yet, but my android phone detects it, so it seems to work fine.

    it seems simple enough to do, but I'm not sure if I should go to my local piercer? thoughts? suggestions?

    I should have an update in a week or so when it's in.

  • if you can get some help from a local body mod professional, that would be ideal. we're working on a procedure document and a legal release form for body mod pros that they can use to help would-be implantees, but it's not ready yet.
  • edited February 2013
    I tried using the chip today, and wondered why it was detected and I could read the ID, but not the data, then I found I can read the data on the nexus S, but not the nexus 4 I'd been using, googling answered why that is, the Mifare Classic doesn't conform to the official NFC standard, but because they were made by the same company that made the readers in older phones, they worked, because the nexus 4 has a reader from a different company, which only supports standards compliant tags, it's not compatible.

    so, there doesn't seem like much point implanting it if it won't work with newer phones. although it still has some use, you can read the tag ID, just not any of the data.

    I don't blame amal, it seems many people where caught by this issue, although he should probably warn people about this issue.

    I still want to get an NFC implant, but want one that works with newer devices, amal, can you supply implants that work with the nexus 4/standards compliant readers?

  • Hi AmmonRa,

    This is actually an old issue, with some false data thrown in. It's obvious to me that the guy who wrote the original post does not know how ISO 14443-A tags work, what the underlying RFID spec is, or how the specs for each of the NFC Forum tag types were created as simple memory constructs for existing ISO standard tag types. Statements like "Mifare Classic NFC Chips and designed them specifically to be compatible with their NXP hardware, but did not design them according to the NFC Forum standards" illustrate this, because the truth of the matter is, no tags have been developed or designed "according to NFC Forum standards"... all NFC tag types have been defined based on popular tag memory structures that have already existed for years and years.

    What he is correct about is that there appears to be an issue with the APIs between the Broadcom hardware and the Android OS, however this is not a hardware limitation. This is apparent because the Mifare's UID bits can still be read from the tag, and the memory blocks that store the UID and MAD of the Mifare Classic S50 1K tag are no different in structure or access protocol than any other memory block. I've heard rumors that Android is working on updating their APIs to re-support Mifare through the Broadcom chipset, but it's just a rumor.

    The bottom line is, Mifare tags like the Mini, S50, S70, and others are not supported as an NFC Forum tag type 1-4, however it has historically been supported in Android OS, Windows Phone, and even BlackBerry. That said, I am working directly with NXP to create a miniaturized NTAG203 IC that can be fit into a bioglass form factor.

    Point taken about warning people though, I will definitely update the product page.

    Since I do not have a Nexus 4 or Nexus 10 to test with, I recommend downloading NXP's TagInfo app; https://play.google.com/store/apps/details?id=com.nxp.taginfolite

    1) Run the app

    2) Go into the menu, then preferences, then change scan level to FULL

    3) Scan the tag and wait for it to fully scan

    4) Tap the share icon and email the data to yourself, then post it!

    If an error comes up instead, post that!

  • note for others, I emailed amal the scan output, but it only showed the chip as not being recognized.

    so, if it's just a software problem, it may be possible to write some kind of 'driver' or interface to make it work.
    here is the relevant part of the android code base:

    the last comment here suggests it could be to do with the (broken) crypto that Mifare Classic uses:

    and here is a link to the crypto algorithm:

    but even if we could make it work (that's a big if, although it's probably possible, it might take a lot of work), I'd be hesitant to implant a non-standards compliant device, since the next gen readers will probably have the same issue.

    you mentioned a NTAG203 version of the implant, is this just a hope, or are you really building such a device? and if so, what kind of ETA are we looking at? months? years?
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